Use After Free in OpenSSL
CVE-2016-6309
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.
Vulnerability class: Use-After-Free
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.702 (99.4th percentile), scored .
High probability of exploitation in the next 30 days — patch promptly. 99th percentile — 99.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.702 · newest: 0.702 · change: 0.000
Affected products
- OpenSSL — versions 1.1.0a
Weakness classification (CWE)
Public proof-of-concept exploits
References
- www.tenable.com/security/tns-2016-20
- www.oracle.com/technetwork/security-advisory/cpujan2018-3236628.html
- www.openssl.org/news/secadv/20160926.txt (Vendor Advisory)
- support.hpe.com/hpsc/doc/public/display
- www-01.ibm.com/support/docview.wss
- www.securitytracker.com/id/1036885 (vdb-entry)
- www.oracle.com/technetwork/security-advisory/cpuoct2016-2881722.html
- www.tenable.com/security/tns-2016-16
- git.openssl.org/
- www.securityfocus.com/bid/93177 (vdb-entry)
Frequently asked questions
- What is CVE-2016-6309?
- CVE-2016-6309 is a critical-severity vulnerability in OpenSSL, classified under Use After Free. CVSS score: 9.8/10. Published 2016-09-26.
- How severe is CVE-2016-6309?
- Critical severity. CVSS v3 base score is 9.8 out of 10.
- Is CVE-2016-6309 known to be exploited?
- 39 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.