How severe is CVE-2025-6966?

CVE-2025-6966 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2025-6966 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-6966?

CVE-2025-6966 primarily affects Ubuntu Python-apt. In total, 41 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-6966?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-6966 have an EU (EUVD) identifier?

Yes. CVE-2025-6966 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-201407.

When was CVE-2025-6966 published?

CVE-2025-6966 was published on 2025-12-05 and last updated on 2026-06-17.

CVE-2025-6966

CVE-2025-6966 is a medium-severity vulnerability in Ubuntu Python-apt with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-476.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v4: 6.9
EPSS exploit prediction: 0% (3rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-201407
Weakness: CWE-476
Affected product: Ubuntu Python-apt
Published: 2025-12-05
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2025-6966?: CVE-2025-6966 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-6966 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-6966?: CVE-2025-6966 primarily affects Ubuntu Python-apt. In total, 41 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-6966?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-6966 have an EU (EUVD) identifier?: Yes. CVE-2025-6966 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-201407.
When was CVE-2025-6966 published?: CVE-2025-6966 was published on 2025-12-05 and last updated on 2026-06-17.

References

Affected products (41)

cpe:2.3:a:ubuntu:python-apt:*:*:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:0.9.3.5:ubuntu1:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:0.9.3.5:ubuntu2:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:0.9.3.11:-:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:0.9.3.11:build1:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1build1:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.1:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.10:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.11:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.2:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.3:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.4:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.5:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.7:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.8:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.9:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.1.0:beta2ubuntu1:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.1.0:beta3:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.1.0:beta4:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.1.0:beta4ubuntu1:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.1.0:beta5:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.1.0:beta5ubuntu1:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:1.6.6:-:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:2.0.1:-:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:2.4.0:\+22.10:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:2.4.0:-:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:2.4.0:ubuntu1:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:2.4.0:ubuntu2:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:2.4.0:ubuntu3:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:2.4.0:ubuntu4:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:2.7.7:-:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:2.7.7:build1:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:2.7.7:ubuntu1:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:2.7.7:ubuntu2:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:2.7.7:ubuntu3:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:2.7.7:ubuntu4:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:2.7.7:ubuntu5:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:3.0.0:-:*:*:*:*:*:*
cpe:2.3:a:ubuntu:python-apt:3.0.0:ubuntu1:*:*:*:*:*:*

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