What is CVE-2025-6966?

CVE-2025-6966 is a medium-severity vulnerability in Canonical Python-Apt, classified under NULL Pointer Dereference. CVSS score: 5.5/10. Published 2025-12-05.

How severe is CVE-2025-6966?

Medium severity. CVSS v3 base score is 5.5 out of 10.

NULL pointer dereference in Canonical Python-Apt

CVE-2025-6966

NULL pointer dereference in TagSection.keys() in python-apt on APT-based Linux systems allows a local attacker to cause a denial of service (process crash) via a crafted deb822 file with a malformed non-UTF-8 key.

Published 2025-12-05 · last modified 2026-09-25.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.001 (3.8th percentile), scored 2026-11-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 4th percentile — 3.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: 0.000

Affected products

Canonical Python-Apt — versions 3.0, 2.7, 2.4
Canonical Ubuntu Linux
Debian Linux — versions 11.0
Ubuntu Python-Apt — versions 0.9.3.5, 0.9.3.11, 1.1.0

Weakness classification (CWE)

CWE-476 — NULL Pointer Dereference

References

bugs.launchpad.net/ubuntu/+source/python-apt/+bug/2091865 (Exploit, Third Party Advisory, Issue Tracking)
af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)

Frequently asked questions

What is CVE-2025-6966?: CVE-2025-6966 is a medium-severity vulnerability in Canonical Python-Apt, classified under NULL Pointer Dereference. CVSS score: 5.5/10. Published 2025-12-05.
How severe is CVE-2025-6966?: Medium severity. CVSS v3 base score is 5.5 out of 10.