CVE-2025-6966 | Null-pointer dereference in python-apt TagSection.keys()

Exp

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 update: 2026-01-07 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-6966 is rated Exploit Available (50/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.01%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2025-6966

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2025-6966

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-12-06 — 0.01% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-6966

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.9 4.0 MEDIUM
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 Click to expand
Attack vector (AV:L)
Attacker needs local access on the target system.
Attack complexity (AC:L)
Exploitation conditions are straightforward and stable.
Attack requirements (AT:N)
No additional preconditions are required beyond normal reachability.
Privileges required (PR:N)
No privileges are required.
User interaction (UI:N)
No user interaction is required.
Vulnerable system confidentiality impact (VC:N)
No confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:N)
No integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:H)
High availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N)
No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.
Exploit maturity (threat) (E:X)
Not defined: no reliable threat intelligence; scoring assumes the worst case (equivalent to Attacked).
Confidentiality requirement (CR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Integrity requirement (IR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Availability requirement (AR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Modified attack vector (MAV:X)
Not defined: scoring uses the Base Attack Vector (AV).
Modified attack complexity (MAC:X)
Not defined: scoring uses the Base Attack Complexity (AC).
Modified attack requirements (MAT:X)
Not defined: scoring uses the Base Attack Requirements (AT).
Modified privileges required (MPR:X)
Not defined: scoring uses the Base Privileges Required (PR).
Modified user interaction (MUI:X)
Not defined: scoring uses the Base User Interaction (UI).
Modified vulnerable system confidentiality impact (MVC:X)
Not defined: scoring uses the Base VC metric.
Modified vulnerable system integrity impact (MVI:X)
Not defined: scoring uses the Base VI metric.
Modified vulnerable system availability impact (MVA:X)
Not defined: scoring uses the Base VA metric.
Modified subsequent system confidentiality impact (MSC:X)
Not defined: scoring uses the Base SC metric.
Modified subsequent system integrity impact (MSI:X)
Not defined: scoring uses the Base SI metric.
Modified subsequent system availability impact (MSA:X)
Not defined: scoring uses the Base SA metric.
Safety (supplemental) (S:X)
Not evaluated.
Automatable (supplemental) (AU:X)
Not evaluated.
Recovery (supplemental) (R:X)
Not evaluated.
Value density (supplemental) (V:X)
Not evaluated.
Vulnerability response effort (supplemental) (RE:X)
Not evaluated.
Provider urgency (supplemental) (U:X)
Not evaluated.
 — — [email protected]
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 3.6 [email protected]

Weakness enumeration for CVE-2025-6966

OS Trackers for CVE-2025-6966

vendor priority summary link
debian not yet assigned CVE-2025-6966 not yet assigned priority: Debian including 1 source packages (python-apt), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 3, open 2. https://security-tracker.debian.org/tracker/CVE-2025-6966
redhat medium — https://access.redhat.com/security/cve/CVE-2025-6966
ubuntu medium CVE-2025-6966 medium priority: Ubuntu including 1 source packages (python-apt), 9 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): released 9. https://ubuntu.com/security/CVE-2025-6966

Affected software / configurations for CVE-2025-6966

Vendor Product Version Raw CPE
ubuntu python-apt < 0.9.3.11 cpe:2.3:a:ubuntu:python-apt:*:*:*:*:*:*:*:*
ubuntu python-apt >= 1.6.0, < 1.6.6 cpe:2.3:a:ubuntu:python-apt:*:*:*:*:*:*:*:*
ubuntu python-apt >= 2.0.0, < 2.0.1 cpe:2.3:a:ubuntu:python-apt:*:*:*:*:*:*:*:*
ubuntu python-apt >= 2.7.0, < 2.7.7 cpe:2.3:a:ubuntu:python-apt:*:*:*:*:*:*:*:*
ubuntu python-apt 0.9.3.5 cpe:2.3:a:ubuntu:python-apt:0.9.3.5:ubuntu1:*:*:*:*:*:*
ubuntu python-apt 0.9.3.5 cpe:2.3:a:ubuntu:python-apt:0.9.3.5:ubuntu2:*:*:*:*:*:*
ubuntu python-apt 0.9.3.11 cpe:2.3:a:ubuntu:python-apt:0.9.3.11:-:*:*:*:*:*:*
ubuntu python-apt 0.9.3.11 cpe:2.3:a:ubuntu:python-apt:0.9.3.11:build1:*:*:*:*:*:*
ubuntu python-apt 1.1.0 cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1:*:*:*:*:*:*
ubuntu python-apt 1.1.0 cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1build1:*:*:*:*:*:*
ubuntu python-apt 1.1.0 cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.1:*:*:*:*:*:*
ubuntu python-apt 1.1.0 cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.10:*:*:*:*:*:*
ubuntu python-apt 1.1.0 cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.11:*:*:*:*:*:*
ubuntu python-apt 1.1.0 cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.2:*:*:*:*:*:*
ubuntu python-apt 1.1.0 cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.3:*:*:*:*:*:*
ubuntu python-apt 1.1.0 cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.4:*:*:*:*:*:*
ubuntu python-apt 1.1.0 cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.5:*:*:*:*:*:*
ubuntu python-apt 1.1.0 cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.7:*:*:*:*:*:*
ubuntu python-apt 1.1.0 cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.8:*:*:*:*:*:*
ubuntu python-apt 1.1.0 cpe:2.3:a:ubuntu:python-apt:1.1.0:beta1ubuntu0.16.04.9:*:*:*:*:*:*
ubuntu python-apt 1.1.0 cpe:2.3:a:ubuntu:python-apt:1.1.0:beta2ubuntu1:*:*:*:*:*:*
ubuntu python-apt 1.1.0 cpe:2.3:a:ubuntu:python-apt:1.1.0:beta3:*:*:*:*:*:*
ubuntu python-apt 1.1.0 cpe:2.3:a:ubuntu:python-apt:1.1.0:beta4:*:*:*:*:*:*
ubuntu python-apt 1.1.0 cpe:2.3:a:ubuntu:python-apt:1.1.0:beta4ubuntu1:*:*:*:*:*:*
ubuntu python-apt 1.1.0 cpe:2.3:a:ubuntu:python-apt:1.1.0:beta5:*:*:*:*:*:*
ubuntu python-apt 1.1.0 cpe:2.3:a:ubuntu:python-apt:1.1.0:beta5ubuntu1:*:*:*:*:*:*
ubuntu python-apt 1.6.6 cpe:2.3:a:ubuntu:python-apt:1.6.6:-:*:*:*:*:*:*
ubuntu python-apt 2.0.1 cpe:2.3:a:ubuntu:python-apt:2.0.1:-:*:*:*:*:*:*
ubuntu python-apt 2.4.0 cpe:2.3:a:ubuntu:python-apt:2.4.0:\+22.10:*:*:*:*:*:*
ubuntu python-apt 2.4.0 cpe:2.3:a:ubuntu:python-apt:2.4.0:-:*:*:*:*:*:*
ubuntu python-apt 2.4.0 cpe:2.3:a:ubuntu:python-apt:2.4.0:ubuntu1:*:*:*:*:*:*
ubuntu python-apt 2.4.0 cpe:2.3:a:ubuntu:python-apt:2.4.0:ubuntu2:*:*:*:*:*:*
ubuntu python-apt 2.4.0 cpe:2.3:a:ubuntu:python-apt:2.4.0:ubuntu3:*:*:*:*:*:*
ubuntu python-apt 2.4.0 cpe:2.3:a:ubuntu:python-apt:2.4.0:ubuntu4:*:*:*:*:*:*
ubuntu python-apt 2.7.7 cpe:2.3:a:ubuntu:python-apt:2.7.7:-:*:*:*:*:*:*
ubuntu python-apt 2.7.7 cpe:2.3:a:ubuntu:python-apt:2.7.7:build1:*:*:*:*:*:*
ubuntu python-apt 2.7.7 cpe:2.3:a:ubuntu:python-apt:2.7.7:ubuntu1:*:*:*:*:*:*
ubuntu python-apt 2.7.7 cpe:2.3:a:ubuntu:python-apt:2.7.7:ubuntu2:*:*:*:*:*:*
ubuntu python-apt 2.7.7 cpe:2.3:a:ubuntu:python-apt:2.7.7:ubuntu3:*:*:*:*:*:*
ubuntu python-apt 2.7.7 cpe:2.3:a:ubuntu:python-apt:2.7.7:ubuntu4:*:*:*:*:*:*
ubuntu python-apt 2.7.7 cpe:2.3:a:ubuntu:python-apt:2.7.7:ubuntu5:*:*:*:*:*:*
ubuntu python-apt 3.0.0 cpe:2.3:a:ubuntu:python-apt:3.0.0:-:*:*:*:*:*:*
ubuntu python-apt 3.0.0 cpe:2.3:a:ubuntu:python-apt:3.0.0:ubuntu1:*:*:*:*:*:*
debian debian_linux 11.0 cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

References for CVE-2025-6966

URL Tags
https://bugs.launchpad.net/ubuntu/+source/python-apt/+bug/2091865 Exploit Issue Tracking Third Party Advisory
https://lists.debian.org/debian-lts-announce/2025/12/msg00019.html Mailing List Third Party Advisory
cvelogic Threat Intelligence