What is CVE-2016-4356?

CVE-2016-4356 is a high-severity vulnerability in Gnupg Libksba, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 7.5/10. Published 2016-06-13.

How severe is CVE-2016-4356?

High severity. CVSS v3 base score is 7.5 out of 10.

Buffer overflow in Gnupg Libksba

CVE-2016-4356

The append_utf8_value function in the DN decoder (dn.c) in Libksba before 1.3.3 allows remote attackers to cause a denial of service (out-of-bounds read) by clearing the high bit of the byte after invalid utf-8 encoded data.

Vulnerability class: Buffer Overflow

Published 2016-06-13 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.029 (86.5th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 87th percentile — 86.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.029 · newest: 0.029 · change: 0.000

Affected products

Gnupg Libksba
Canonical Ubuntu Linux — versions 12.04, 14.04

Weakness classification (CWE)

CWE-119 — Improper Restriction of Operations within the Bounds of a Memory Buffer

References

www.openwall.com/lists/oss-security/2016/05/10/3 (mailing-list)
www.ubuntu.com/usn/USN-2982-1 (vendor-advisory)
www.openwall.com/lists/oss-security/2016/04/29/5 (mailing-list)
www.openwall.com/lists/oss-security/2016/04/29/8 (mailing-list)
git.gnupg.org/cgi-bin/gitweb.cgi
security.gentoo.org/glsa/201604-04 (vendor-advisory)

Frequently asked questions

What is CVE-2016-4356?: CVE-2016-4356 is a high-severity vulnerability in Gnupg Libksba, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 7.5/10. Published 2016-06-13.
How severe is CVE-2016-4356?: High severity. CVSS v3 base score is 7.5 out of 10.