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Fencer Intel
medium 5.5

CVE-2025-6966 json

Null-pointer dereference in python-apt TagSection.keys()

published 11mo ago modified last mo. also EUVD-2025-201407

cvss
5.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 4%
public exploits
0
none known

Summary

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.

Patch / fix

  • Canonical python-apt 0.9.3.5ubuntu3+esm5, 1.1.0~beta1ubuntu0.16.04.12+esm1, 1.6.6ubuntu0.1~esm1, 2.0.1ubuntu0.20.04.1+esm1, 2.4.0ubuntu4.1, 2.7.7ubuntu5.1, 3.0.0ubuntu0.25.04.1, 3.0.0ubuntu1.1
  • python-apt Debian 14 3.1.0

debian advisories DEBIAN-CVE-2025-6966

  • python-apt Ubuntu 22.04 LTS 2.4.0ubuntu4.1
  • python-apt Ubuntu 24.04 LTS 2.7.7ubuntu5.1
  • python-apt Ubuntu 25.10 3.0.0ubuntu1.1
  • python-apt Ubuntu Pro 14.04 LTS 0.9.3.5ubuntu3+esm5
  • python-apt Ubuntu Pro 16.04 LTS 1.1.0~beta1ubuntu0.16.04.12+esm1
  • python-apt Ubuntu Pro 18.04 LTS 1.6.6ubuntu0.1~esm1
  • python-apt Ubuntu Pro 20.04 LTS 2.0.1ubuntu0.20.04.1+esm1

ubuntu advisories UBUNTU-CVE-2025-6966

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2025-6966 updated cvss 4.0

python-apt: python-apt: NULL pointer dereference leads to local denial of service

  • Red Hat All currently supported Red Hat products
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
11mo ago

Exploit prediction

0.16% chance of exploitation in the next 30 days, higher than 4% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • bugs.launchpad.net https://bugs.launchpad.net/ubuntu/+source/python-apt/+bug/2091865 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 6.9 CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CNA 4.0 6.9 CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products

  • Canonical python-apt

Classification

Weakness

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.