CVE-2016-6309

critical
Published 2016-09-26 · Modified 2026-05-06
CVSS v3
9.8
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v2
10.0
VIR risk
9.8

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.

Predictions

Exploit likelihood
97%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2016-6309

vendor Authored 2026-05-27

Vendor advisory: secalert@redhat.com — https://www.openssl.org/news/secadv/20160926.txt

OS impact

OSVersionStatusFixed in
arch archaffected
debian debianbookwormfixed0
debian debianbullseyefixed0
debian debianforkyfixed0
debian debiansidfixed0
debian debiantrixiefixed0

Application impact

VendorProductVersionsFixed
openssl opensslopenssl1.1.0a

References

CWEs

CWE-416

Verify integrity in audit chain (admin only). AS-IS.