CVE-2016-6309

Severity: critical (CVSS 9.8 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 70.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2016-09-26 · updated 2026-06-17
Weakness: CWE-416

Description

statem/statem.c in OpenSSL 1.1.0a does not consider memory-block movement after a realloc call, which allows remote attackers to cause a denial of service (use-after-free) or possibly execute arbitrary code via a crafted TLS session.

Affected products

OpenSSL: 1.1.0a

References

http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10759
http://www-01.ibm.com/support/docview.wss?uid=swg21995039
http://www.oracle.com/technetwork/security-advisory/cpuapr2018-3678067.html
http://www.oracle.com/technetwork/security-advisory/cpujan2018-3236628.html
http://www.oracle.com/technetwork/security-advisory/cpujul2017-3236622.html
http://www.oracle.com/technetwork/security-advisory/cpuoct2016-2881722.html
http://www.securityfocus.com/bid/93177
http://www.securitytracker.com/id/1036885
https://bto.bluecoat.com/security-advisory/sa132
https://git.openssl.org/?p=openssl.git%3Ba=commit%3Bh=acacbfa7565c78d2273c0b2a2e5e803f44afefeb
https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03856en_us
https://www.openssl.org/news/secadv/20160926.txt

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