View source for OpenSSL

{{Distinguish|OpenSSH}}
{{Infobox software
| name                 = OpenSSL
| logo                 = OpenSSL logo.png
| logo size            = 240px
| screenshot           =
| caption              =
| developer            = The OpenSSL Project
| released             = 1998
| operating_system     = <!--Nothing; it is a library, not a full app-->
| programming_language = [[C (programming language)|C]], [[Assembly language|assembly]]
| genre                = [[Library (computer science)|Security library]]
| license              = [[Apache License]]&nbsp;1.0 and four-clause [[BSD License]]
| website              = {{URL|https://www.openssl.org/}}
}}

'''OpenSSL''' is a software library to be used in applications that need to secure communications over [[computer network]]s against eavesdropping or need to ascertain the identity of the party at the other end. It has found wide use in internet web servers, serving a majority of all web sites.

OpenSSL contains an [[open-source]] implementation of the [[Transport Layer Security|SSL and TLS]] protocols.  The core [[library (computer science)|library]], written in the [[C (programming language)|C programming language]], implements basic [[cryptographic]] functions and provides various utility functions. Wrappers allowing the use of the OpenSSL library in a variety of computer languages are available.

Versions are available for most [[Unix]] and [[Unix-like]] operating systems (including [[Solaris (operating system)|Solaris]], [[Linux]], [[macOS]], [[QNX]], and the various open-source [[BSD]] operating systems), [[OpenVMS]] and [[Microsoft Windows]]. IBM provides a port for the [[IBM i|System i]] (OS/400).

== Project history ==

The OpenSSL project was founded in 1998 to invent a free set of encryption tools for the code used on the Internet. It is based on a fork of [[SSLeay]] by Eric Andrew Young and Tim Hudson, development of which unofficially ended on December 17, 1998, when Young and Hudson both started to work for [[RSA Security]].

The OpenSSL project management team consists of four people, and the entire development group consists of 11 members, out of which 10 are volunteers; there is only one full-time employee,  Stephen Henson, the lead developer.<ref name="wsj" />

The project has a budget of less than $1 million a year and relies in part on donations. Steve Marquess, a former CIA consultant in Maryland started the foundation for donations and consultancy contracts and garnered sponsorship from the [[United States Department of Homeland Security]] and the [[United States Department of Defense]].<ref name=wsj>{{cite news|last=Yadron|first=Danny|title=Internet Security Relies on Very Few|url=https://web.archive.org/web/20140426085925/https://online.wsj.com/news/articles/SB20001424052702303873604579495362672447986|accessdate=10 May 2017|newspaper=WSJ.com|date=11 April 2014}}</ref>

== Major version releases ==

<!--Template:Version - for version & release history. Documentation & examples: http://en.wikipedia.org/wiki/Template:Version-->
{|class="wikitable" style="min-width:40%"
|+ OpenSSL release history<ref name=changelog>{{cite web|title=OpenSSL – Changelog|url=https://www.openssl.org/news/changelog.html|publisher=OpenSSL Software Foundation|accessdate=2016-09-26}}</ref><ref name=releasestrat>{{cite web|title=OpenSSL – Release Strategy|url=https://www.openssl.org/policies/releasestrat.html|publisher=OpenSSL Software Foundation|accessdate=2016-09-26}}</ref>
|-
! Version !! Original release date !! Comment !! Last minor version
|-
| {{Version |o |0.9.1}}
| December 23, 1998
| align="right" |
* Official start of the OpenSSL project
| 0.9.1c (December 23, 1998)
|-
| {{Version |o |0.9.2}}
| March 22, 1999
| align="right" |
* Successor of 0.9.1c
| 0.9.2b (April 6, 1999)
|-
| {{Version |o |0.9.3}}
| May 25, 1999
| align="right" |
* Successor of 0.9.2b
| 0.9.3a (May 27, 1999)
|-
| {{Version |o |0.9.4}}
| August 9, 1999
| align="right" |
* Successor of 0.9.3a
| 0.9.4 (August 9, 1999)
|-
| {{Version |o |0.9.5}}
| February 28, 2000
| align="right" |
* Successor of 0.9.4
| 0.9.5a (April 1, 2000)
|-
| {{Version |o |0.9.6}}
| September 24, 2000
| align="right" |
* Successor of 0.9.5a
| 0.9.6m (March 17, 2004)
|-
| {{Version |o |0.9.7}}
| December 31, 2002
| align="right" |
* Successor of 0.9.6m
| 0.9.7m (February 23, 2007)
|-
| {{Version |o |0.9.8}}
| July 5, 2005
| align="right" |
* Successor of 0.9.7m
| 0.9.8zh (December 3, 2015)
|-
| {{Version |o |1.0.0}}
| March 29, 2010
| align="right" |
* Successor of 0.9.8n
| 1.0.0t (December 3, 2015)
|-
| {{Version |o |1.0.1}}<ref name=openssl_1.0.1_notes>{{cite web|url=https://www.openssl.org/news/openssl-1.0.1-notes.html|title=OpenSSL 1.0.1 Series Release Notes|accessdate=2017-02-20}}</ref>
| March 14, 2012
| align="right" |
* Successor of 1.0.0
* Supported until December 31, 2016
* RFC 6520 TLS/DTLS heartbeat support.
* [[SCTP]] support.
* RFC 5705 TLS key material exporter.
* RFC 5764 DTLS-SRTP negotiation.
* [[Next Protocol Negotiation]].
* PSS signatures in certificates, requests and [[certificate revocation list]]s (CRL)s.
* Support for password based recipient info for CMS.
* Support TLS v1.2 and TLS v1.1.
* Preliminary FIPS capability for unvalidated 2.0 FIPS module.
* [[Secure Remote Password protocol]] (SRP) support.
| 1.0.1u (September 22, 2016)
|-
| {{Version |co |1.0.2}}<ref name=openssl_1.0.2_notes>{{cite web|url=https://www.openssl.org/news/openssl-1.0.2-notes.html|title=OpenSSL 1.0.2 Series Release Notes|accessdate=2017-02-20}}</ref>
| January 22, 2015
| align="right" |
* Successor of 1.0.1
* Supported until December 31, 2019 (Long Term Support)
* Suite B support for TLS 1.2 and DTLS 1.2
* Support for DTLS 1.2
* TLS automatic [[elliptic curve]] (EC) curve selection.
* API to set TLS supported signature algorithms and curves
* SSL_CONF configuration API.
* TLS [[ECC Brainpool|Brainpool]] support.
* [[ALPN]] support.
* CMS support for [[RSA-PSS]], [[RSA-OAEP]], [[ECDH]] and [[X9.42]] DH.
| 1.0.2k (January 26, 2017)
|-
| {{Version |c|1.1.0}}<ref name=openssl_1.1.0_notes>{{cite web|url=https://www.openssl.org/news/openssl-1.1.0-notes.html|title=OpenSSL 1.1.0 Series Release Notes|accessdate=2017-02-20}}</ref>
| August 25, 2016
| align="right" |
* Successor of 1.0.2h
* Supported until April 30, 2018
* Support for [[ChaCha20]]-[[Poly1305]] (RFC 7539)
* Support for extended master secret
* Support for [[X25519]]
* Support for [[DNS-based Authentication of Named Entities|DANE]] and [[Certificate Transparency]]
* [[CCM mode|CCM]] Ciphersuites
* SSLv2 removed
* Kerberos ciphersuite support removed
* RC4 and 3DES removed from DEFAULT ciphersuites in libssl
* Remove DSS, SEED, IDEA, CAMELLIA, and AES-CCM from the DEFAULT cipherlist.
* 40 and 56 bit cipher support removed from libssl
| 1.1.0e (February 16, 2017)
|-
| {{Version | p|1.1.1}}<ref>https://www.openssl.org/news/changelog.html#x0</ref>
|
|
|
|-
| colspan="4" | <small>{{Version |l |show=111111}}</small>
|}

== Algorithms ==

OpenSSL supports a number of different cryptographic algorithms:
; [[Cipher]]s:
: [[Advanced Encryption Standard|AES]], [[Blowfish (cipher)|Blowfish]], [[Camellia (cipher)|Camellia]], [[SEED]], [[CAST-128]], [[Data Encryption Standard|DES]], [[International Data Encryption Algorithm|IDEA]], [[RC2]], [[RC4]], [[RC5]], [[Triple DES]], [[GOST (block cipher)|GOST 28147-89]]<ref name="gost">{{cite web |url=http://cvs.openssl.org/fileview?f=openssl/engines/ccgost/README.gost |title=GOST engine OpenSSL 1.0.0 README |publisher=cvs.openssl.org }}</ref>
; [[Cryptographic hash function]]s:
: [[MD5]], [[MD4]], [[MD2 (cryptography)|MD2]], [[SHA-1]], [[SHA-2]], [[RIPEMD-160]], [[MDC-2]], [[GOST (hash function)|GOST R 34.11-94]],<ref name="gost" /> [[BLAKE (hash function)#BLAKE2|BLAKE2]]
; [[Public-key cryptography]]:
: [[RSA (algorithm)|RSA]], [[Digital Signature Algorithm|DSA]], [[Diffie–Hellman key exchange]],  [[Elliptic curve cryptography|Elliptic curve]], [[GOST R 34.10-2001]]<ref name="gost" />

([[Perfect forward secrecy]] is supported using [[elliptic curve Diffie–Hellman]] since version 1.0.<ref>{{cite web|url=http://googleonlinesecurity.blogspot.com.au/2011/11/protecting-data-for-long-term-with.html|title=Protecting data for the long term with forward secrecy|accessdate=2012-11-05}}</ref>)

== FIPS 140-2 compliance ==

{{As of|2012|12}}, OpenSSL is one of two [[open source]] programs to be involved with validation under the [[FIPS 140-2]] computer security standard by the [[National Institute of Standards and Technology]]'s (NIST) [[Cryptographic Module Validation Program]] (CMVP).<ref>[http://csrc.nist.gov/groups/STM/cmvp/documents/140-1/1401val2012.htm Validated FIPS 140-1 and FIPS 140-2 Cryptographic Modules]. NIST. Retrieved 2012-12-19.</ref> (OpenSSL itself is not validated, but a component called the OpenSSL FIPS Object Module, based on OpenSSL, was created to provide many of the same capabilities).<ref>{{cite web |url=https://www.openssl.org/docs/fips/fipsnotes.html |title=Important Notes about OpenSSL and FIPS 140-2 |publisher=openssl.org}}</ref>

A certificate was first awarded in January 2006 but revoked in July 2006 "when questions were raised about the validated module’s interaction with outside software." The certification was reinstated in February 2007.<ref>{{cite web |url=http://www.gcn.com/online/vol1_no1/43142-1.html |title=NIST recertifies open source encryption module |publisher=gcn.com}}</ref>

== Licensing ==

OpenSSL is "dual licensed" under the OpenSSL License and the SSLeay License.<ref>{{cite web |url=https://www.openssl.org/source/license.html |title=OpenSSL: Source, License |publisher=openssl.org}}</ref> The OpenSSL License is [[Apache License]] 1.0 and SSLeay License bears some similarity to a 4-clause [[BSD License]]. The common usage of the term ''dual-license'' is that the user may pick which license they wish to use. However, OpenSSL documentation uses the term ''dual-license'' to mean that both licenses apply.

As the OpenSSL License is [[Apache License]] 1.0, but not Apache License 2.0, it requires the phrase "this product includes software developed by the OpenSSL Project for use in the OpenSSL Toolkit" to appear in advertising material and any redistributions (Sections 3 and 6 of the OpenSSL License). Due to this restriction, the OpenSSL License and the Apache License 1.0 are incompatible with the [[GNU General Public License|GPL]].<ref>{{cite web |url=http://www.fsf.org/licensing/licenses |title=Licenses – Free Software Foundation |publisher=fsf.org}}</ref>
Some GPL developers have added an ''OpenSSL exception'' to their licenses specifically allowing OpenSSL to be used with their system. GNU [[Wget]] and [[climm]] both use such exceptions.<ref>{{cite web |url=http://users.ugent.be/~bpuype/wget |title=WGET 1.10.2 for Windows (win32) |publisher=users.ugent.be}}</ref><ref>{{cite web |url=http://www.climm.org/download.shtml.en |title=Releases of source and binaries |publisher=climm.org |accessdate=30 November 2010}}</ref> Some packages (like [[Deluge (software)|Deluge]]) explicitly modify the GPL license by adding an extra section at the beginning of the license documenting the exception.<ref>{{cite web |url=http://git.deluge-torrent.org/deluge/plain/LICENSE |title=Deluge LICENSE file |publisher=deluge-torrent.org |accessdate=24 January 2013}}</ref> Other packages use the [[GNU Lesser General Public License|LGPL]]-licensed [[GnuTLS]] and [[Mozilla Public License|MPL]]-licensed [[Network Security Services|NSS]], both of which perform the same task.

OpenSSL announced in August 2015 that it would require most contributors to sign a [[Contributor License Agreement]] (CLA), and that OpenSSL would eventually be [[Software relicensing|relicensed]] under the terms of [[Apache License&nbsp;2.0]].<ref>{{cite web
 | url = https://www.openssl.org/blog/blog/2015/08/01/cla/
 | title = License Agreements and Changes Are Coming
 | date = 1 August 2015 | accessdate = 23 August 2015
 | last = Salz | first = Rich | website = openssl.org
}}</ref> This process commenced in March 2017.<ref>{{Cite web |url=https://www.coreinfrastructure.org/news/announcements/2017/03/openssl-re-licensing-apache-license-v-20-encourage-broader-use-other-foss |title=OpenSSL Re-licensing to Apache License v. 2.0 To Encourage Broader Use with Other FOSS Projects and Products}}</ref>

== Notable vulnerabilities ==

=== Timing attacks on RSA Keys ===

On March 14, 2003, a timing attack on RSA keys was discovered, which meant a vulnerability within OpenSSL versions 0.9.7a and 0.9.6. This vulnerability was assigned the identifier CAN-2003-0147 by the [[Common Vulnerabilities and Exposures]] (CVE) project. [[RSA blinding attack|RSA blinding]] was not turned on by default by OpenSSL, since it is not easily possible to when providing SSL or TLS using OpenSSL. Almost all SSL enabled Apaches were affected, along with many other applications of OpenSSL. Timing differences on the number of extra reductions along and use of Karatsuba and normal integer multiplication algorithms meant that it was possible for local and remote attackers to obtain the private key of the server.{{citation needed|date=April 2014}}

=== Denial of Service ASN.1 parsing ===

OpenSSL 0.9.6k had a bug where certain [[ASN.1]] sequences triggered a large number of recursions on Windows machines, discovered on November 4, 2003. Windows could not handle large recursions correctly, so OpenSSL would crash as a result. Being able to send arbitrary large numbers of ASN.1 sequences would cause OpenSSL to crash as a result. A [[client certificate]] to a SSL/TLS enabled server could accept ASN.1 sequences and crash.{{citation needed|date=April 2014}}

=== OCSP stapling vulnerability ===

When creating a handshake, the client could send an incorrectly formatted ClientHello message, leading to OpenSSL parsing more than the end of the message. Assigned the identifier CVE-2011-0014 by the CVE project, this affected all OpenSSL versions 0.9.8h to 0.9.8q and OpenSSL 1.0.0 to 1.0.0c. Since the parsing could lead to a read on an incorrect memory address, it was possible for the attacker to cause a DOS. It was also possible that some applications expose the contents of parsed OCSP extensions, leading to an attacker being able to read the contents of memory that came after the ClientHello.<ref>{{cite web|title=OpenSSL Updates Fix Critical Security Vulnerabilities [09 Aug 2014]|url=https://blogs.comodo.com/it-security/openssl-updates-fix-critical-security-vulnerabilities/|accessdate=25 Aug 2014}}</ref>

=== ASN.1 BIO vulnerability ===

When using Basic Input/Output (BIO)<ref>{{cite web |url=https://tools.cisco.com/security/center/viewAlert.x?alertId=25706 |title=OpenSSL ASN.1 asn1_d2i_read_bio() Heap Overflow Vulnerability |publisher=Cisco}}</ref> or FILE based functions to read untrusted [[Distinguished Encoding Rules|DER]] format data, OpenSSL is vulnerable. This vulnerability was discovered on April 19, 2012, and was assigned the CVE identifier CVE-2012-2110. While not directly affecting the SSL/TLS code of OpenSSL, any application that was using ASN.1 functions (particularly d2i_X509 and d2i_PKCS12) were also not affected.<ref>{{cite web |url=https://www.openssl.org/news/secadv_20120419.txt |title=ASN1 BIO vulnerability |publisher=OpenSSL}}</ref>

=== SSL, TLS and DTLS Plaintext Recovery Attack ===

In handling CBC cipher-suites in SSL, TLS, and DTLS, OpenSSL was found to be vulnerable to a timing attack which arises during the MAC processing. This was found by Nadhem Alfardan and Kenny Paterson, who published their findings<ref>http://www.isg.rhul.ac.uk/tls/</ref> on February 5, 2013. The vulnerability was assigned the CVE identifier CVE-2013-0169. All versions of OpenSSL were affected, and it was only partially mitigated by the use of the OpenSSL FIPS Object Module and the FIPS mode of operation is enabled.{{citation needed|date=April 2014}}

=== Predictable private keys (Debian-specific) ===

OpenSSL's pseudo-[[random number generator]] acquires entropy using complex programming methods, described{{by whom?|date=March 2017}} as poor coding practice. In order to keep associated warnings from being issued by the [[Valgrind]] analysis tool, a maintainer of the [[Debian]] distribution applied a [[patch (computing)|patch]] to the Debian's variant of the OpenSSL suite, which inadvertently broke its random number generator by limiting the overall number of private keys it could generate to 32,768.<ref>{{Cite web |title=research!rsc: Lessons from the Debian/OpenSSL Fiasco |url=http://research.swtch.com/openssl |website=research.swtch.com |accessdate=2015-08-12}}</ref><ref>{{Cite web |title=SSLkeys - Debian Wiki |url=https://wiki.debian.org/SSLkeys |website=debian.org |accessdate=2015-06-19}}</ref> The broken version was included in the Debian release of September 17, 2006 (version 0.9.8c-1), also compromising other Debian-based distributions, for example [[Ubuntu (operating system)|Ubuntu]]. Any key generated with the broken random number generator was compromised, as well as the data encrypted with such keys;{{Citation needed|reason=DSA keys are known bad, but others?|date=April 2014}} moreover, ready-to-use [[exploit (computer security)|exploits]] are easily available.<ref>{{Cite web |title=Debian OpenSSL –  Predictable PRNG Bruteforce SSH Exploit Python –  Exploits Database |url=https://www.exploit-db.com/exploits/5720/ |website=exploit-db.com |accessdate=2015-08-12}}</ref>

The error was reported by Debian on May 13, 2008.  On the Debian&nbsp;4.0 distribution (etch), these problems were fixed in version 0.9.8c-4etch3, while fixes for the Debian&nbsp;5.0 distribution (lenny) were provided in version 0.9.8g-9.<ref name="dsa-1571-1">{{cite web |title=DSA-1571-1 openssl – predictable random number generator |url=http://www.debian.org/security/2008/dsa-1571 |publisher=[[Debian]] |date=May 13, 2008 }}</ref>

=== {{anchor|Heartbleed bug}}Heartbleed ===

{{Main article|Heartbleed}}

[[File:Heartbleed.svg|thumb|140px|A logo representing the Heartbleed bug]]

OpenSSL versions 1.0.1 through 1.0.1f had a severe memory handling [[software bug|bug]] in their implementation of the [[Transport Layer Security|TLS]] Heartbeat Extension that could be used to reveal up to 64&nbsp;[[Kibibyte|KB]] of the application's memory with every [[heartbeat (computing)|heartbeat]]<ref>{{cite web|title=OpenSSL Security Advisory [07 Apr 2014]|url=https://www.openssl.org/news/secadv_20140407.txt|author=OpenSSL.org|accessdate=9 April 2014|date=7 April 2014}}</ref><ref>{{Cite web| last = OpenSSL| title = TLS heartbeat read overrun (CVE-2014-0160)| accessdate = 2014-04-08| date = 2014-04-07| url = https://www.openssl.org/news/secadv_20140407.txt}}</ref> (CVE-2014-0160). By reading the memory of the web server, attackers could access sensitive data, including the server's [[public-key cryptography|private key]].<ref name="hb">{{Cite web| last = Codenomicon Ltd| title = Heartbleed Bug| accessdate = 2014-04-08| date = 2014-04-08| url = http://heartbleed.com/}}</ref> This could allow attackers to decode earlier [[eavesdropping|eavesdropped]] communications if the encryption protocol used does not ensure [[perfect forward secrecy]]. Knowledge of the private key could also allow an attacker to mount a [[man-in-the-middle attack]] against any future communications.<ref>{{cite web|title=Man in Middle Attacks [04 Jun 2014]|url=https://blogs.comodo.com/it-security/openssl-vulnerability-exploited-man-middle-attacks/|accessdate=25 Aug 2014}}</ref> The vulnerability might also reveal unencrypted parts of other users' sensitive requests and responses, including [[session cookie]]s and passwords, which might allow attackers to [[Session hijacking|hijack the identity]] of another user of the service.<ref name="ipsec">{{cite web |url=http://ipsec.pl/ssl-tls/2014/why-heartbleed-dangerous-exploiting-cve-2014-0160.html |title=Why Heartbleed is dangerous? Exploiting CVE-2014-0160 |year=2014 |publisher=IPSec.pl}}</ref>

At its disclosure on April 7, 2014, around 17% or half a million of the Internet's secure [[web servers]] certified by [[Certificate authority|trusted authorities]] were believed to have been vulnerable to the attack.<ref>{{cite web|last=Mutton|first=Paul|title=Half a million widely trusted websites vulnerable to Heartbleed bug|url=http://news.netcraft.com/archives/2014/04/08/half-a-million-widely-trusted-websites-vulnerable-to-heartbleed-bug.html|publisher=Netcraft Ltd.|accessdate=8 April 2014|date=8 April 2014}}</ref> However, Heartbleed can affect both the server and client.

=== {{anchor|CVE-2014-0224}}CCS Injection Vulnerability ===

CCS Injection Vulnerability (CVE-2014-0224) is a security bypass vulnerability that exists in OpenSSL. The vulnerability is due to a weakness in OpenSSL methods used for keying material.<ref>{{cite web |url=http://www.cyberoam.com/blog/openssl-continues-to-bleed-out-more-flaws-more-critical-vulnerabilities-found/ |title=OpenSSL continues to bleed out more flaws – more critical vulnerabilities found |year=2014 |publisher=Cyberoam Threat Research Labs}}</ref>

This vulnerability can be exploited through the use of a man-in-the-middle attack,<ref>{{cite web |url=https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2014-0224 |title=CVE-2014-0224 |year=2014 |publisher=CVE}}</ref> where an attacker may be able to decrypt and modify traffic in transit. A remote unauthenticated attacker could exploit this vulnerability by using a specially crafted handshake to force the use of weak keying material. Successful exploitation could lead to a security bypass condition where an attacker could gain access to potentially sensitive information. The attack can only be performed between a vulnerable client ''and'' server.

OpenSSL clients are vulnerable in all versions of OpenSSL before the versions 0.9.8za, 1.0.0m and 1.0.1h. Servers are only known to be vulnerable in OpenSSL 1.0.1 and 1.0.2-beta1. Users of OpenSSL servers earlier than 1.0.1 are advised to upgrade as a precaution.<ref>{{cite web |url=https://www.openssl.org/news/secadv_20140605.txt |title=OpenSSL Security Advisory [05 Jun 2014] |year=2014 |publisher=OpenSSL}}</ref>

=== {{anchor|CVE-2015-0291}}ClientHello sigalgs DoS ===

This vulnerability (CVE-2015-0291) allows anyone to take a certificate, read its contents and modify it accurately to abuse the vulnerability causing a certificate to crash a client or server. If a client connects to an OpenSSL 1.0.2 server and renegotiates with an invalid signature algorithms extension, a null-pointer dereference will occur. This can cause a DoS attack against the server.

A Stanford Security researcher, David Ramos had a private exploit and presented it before the OpenSSL team where they patched the issue.

OpenSSL classified the bug as a high-severity issue, noting version 1.0.2 was found vulnerable.<ref>{{cite web |url=http://freedomhacker.net/openssl-patches-severe-denial-of-service-vulnerability-3818/ |title=OpenSSL Patches Severe Denial-of-Service Vulnerability [20 March 2015] |year=2015 |publisher=Brandon Stosh}}</ref>

=== {{anchor|CVE-2016-0701}}Key Recovery Attack on Diffie Hellman small subgroups ===

This vulnerability (CVE-2016-0701) allows, when some particular circumstances are met, to recover the OpenSSL server's private Diffie–Hellman key. An Adobe System Security researcher, Antonio Sanso, privately reported the vulnerability.

OpenSSL classified the bug as a high-severity issue, noting only version 1.0.2 was found vulnerable.<ref>{{cite web |url=http://arstechnica.com/security/2016/01/high-severity-bug-in-openssl-allows-attackers-to-decrypt-https-traffic/ |title= High-severity bug in OpenSSL allows attackers to decrypt HTTPS traffic [28 Jan 2016] |year=2016}}</ref>

== Forks ==

=== {{Anchor|assl}}Agglomerated SSL ===

In 2009, after frustrations with the original OpenSSL API, Marco Peereboom, an OpenBSD developer at the time, forked the original API by creating Agglomerated SSL (assl), which reuses OpenSSL API under the hood, but provides a much simpler external interface.<ref>{{cite web |url= http://ports.su/security/assl |title= security/assl: assl-1.5.0p0v0 – hide awful SSL API in a sane interface |work= [[OpenBSD ports]] |date= 2014-05-22 |accessdate= 2015-02-10 }}</ref>

=== LibreSSL ===

{{Main article|LibreSSL}}

In April 2014 in the wake of Heartbleed, members of the [[OpenBSD]] project [[fork (software development)|fork]]ed OpenSSL starting with the 1.0.1g branch, to create a project named [[LibreSSL]].<ref name="fork">{{cite web |url=http://www.undeadly.org/cgi?action=article&sid=20140415093252&mode=expanded |title= OpenBSD has started a massive strip-down and cleanup of OpenSSL |date=2014-04-15| work=OpenBSD journal}}</ref> In the first week of pruning the OpenSSL's [[codebase]], more than 90,000 lines of C code had been removed from the fork.<ref>{{cite web|title= OpenBSD forks, prunes, fixes OpenSSL |url=http://www.zdnet.com/openbsd-forks-prunes-fixes-openssl-7000028613/|publisher=ZDNet|accessdate=21 April 2014|date=21 April 2014}}</ref>

=== {{Anchor|BORINGSSL}}BoringSSL ===

In June 2014, [[Google]] announced its own fork of OpenSSL dubbed BoringSSL.<ref>https://boringssl.googlesource.com/boringssl/ BoringSSL</ref> Google plans to co-operate with OpenSSL and LibreSSL developers.<ref>{{cite web |title=Google unveils independent 'fork' of OpenSSL called 'BoringSSL' |date=2014-06-21 |work=Ars Technica |url=http://arstechnica.com/security/2014/06/google-unveils-independent-fork-of-openssl-called-boringssl/}}</ref><ref>{{cite web |title=BoringSSL|date=2014-06-20|work=Adam Langley's Weblog |url=https://www.imperialviolet.org/2014/06/20/boringssl.html}}</ref><ref>https://nakedsecurity.sophos.com/2014/06/24/boringssl-wants-kill-the-excitement-that-led-to-heartbleed/</ref>

== See also ==

{{Portal|Free software|Cryptography}}
* [[Comparison of TLS implementations]]
* [[Comparison of cryptography libraries]]
* [[POSSE project]]
* [[wolfSSL]]

== References ==

{{Reflist|}}

== External links ==

{{Commons category}}
* {{Official website|https://www.openssl.org/}}
* [https://www.openssl.org/docs/manpages.html OpenSSL Manpages]
* [http://h71000.www7.hp.com/doc/83final/ba554_90007/ch04s03.html OpenSSL Programming Guide]
* [https://people.gnome.org/~markmc/openssl-and-the-gpl.html The OpenSSL License and the GPL] by Mark McLoughlin
* [https://www.ibm.com/developerworks/linux/library/l-openssl/index.html OpenSSL programming tutorial]
* [https://wiki.openssl.org/index.php/Main_Page OpenSSL Community Wiki]


==Pranala Menarik==

* [[OpenSSL: Essentials]]