Skip to main content

Python tarfile CVE-2025-13462

LOW
Improper Input Validation (CWE-20)
2026-03-12 cna@python.org
2.0
CVSS 4.0 · Vendor: python

Severity by source

Vendor (python) PRIMARY
2.0 LOW
CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/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
vuln.today AI
2.5 LOW

Local vector because attacker must control archive input; PR:L since application-level access is needed; impact limited to low integrity via type misclassification with no confidentiality or availability effect.

3.1 AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
4.0 AV:L/AC:H/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

Primary rating from Vendor (python).

CVSS VectorVendor: python

Attack Vector
Local
Attack Complexity
High
Privileges Required
Low
User Interaction
None
Scope
X

Lifecycle Timeline

5
Source Code Evidence Fetched
Jul 24, 2026 - 08:19 vuln.today
CVSS changed
May 01, 2026 - 16:22 NVD
2.0 (LOW)
Analysis Generated
Mar 12, 2026 - 19:57 vuln.today
CVE Published
Mar 12, 2026 - 18:16 cve.org
LOW 2.0
CVE Published
Mar 12, 2026 - 18:16 nvd
N/A

DescriptionCVE.org

The "tarfile" module would still apply normalization of AREGTYPE (\x00) blocks to DIRTYPE, even while processing a multi-block member such as GNUTYPE_LONGNAME or GNUTYPE_LONGLINK. This could result in a crafted tar archive being misinterpreted by the tarfile module compared to other implementations.

AnalysisAI

Python's tarfile module incorrectly applies AREGTYPE-to-DIRTYPE normalization while processing multi-block GNU extension headers (GNUTYPE_LONGNAME and GNUTYPE_LONGLINK), causing crafted tar archives to be misinterpreted relative to other tar implementations. A regular file with a long name whose intermediate path component ends in a slash can be incorrectly classified as a directory (DIRTYPE), creating a discrepancy that may undermine type-based security checks in downstream archive-processing code. No public exploit is identified, EPSS stands at 0.04% (12th percentile), and this CVE is not in CISA KEV, reflecting negligible real-world exploitation pressure at time of analysis.

Technical ContextAI

The Python tarfile module parses tar archives according to POSIX/GNU tar specifications. The old v7 tar format used AREGTYPE (\x00) for both regular files and directories, relying on a trailing slash in the entry name to distinguish directories; modern implementations normalize AREGTYPE blocks with trailing-slash names to DIRTYPE. GNU tar extended this with GNUTYPE_LONGNAME and GNUTYPE_LONGLINK header types to support names exceeding 100 characters, using follow-up header blocks that carry intermediate name fragments. The root cause (CWE-20: Improper Input Validation) is that the AREGTYPE-to-DIRTYPE normalization was applied unconditionally to every parsed header block, including these follow-up blocks. A follow-up block carrying an intermediate path component ending in a slash would satisfy the heuristic and be incorrectly normalized. The fix - confirmed by PR #143934 - introduces a dircheck parameter that disables the normalization when parsing follow-up headers (dircheck=False in _frombuf and _fromtarfile), protecting GNUTYPE_LONGNAME and GNUTYPE_LONGLINK processing paths. Affected products span all Python versions per CPE (cpe:2.3:a:python:python:*) with specific enumeration of 3.15.0 alpha1 through alpha7.

RemediationAI

Upstream fix is available via CPython pull request #143934 (https://github.com/python/cpython/pull/143934), applied across multiple branches; however, specific tagged patched release versions are not confirmed in the available data and must be verified through the Python security announcement at https://mail.python.org/archives/list/security-announce@python.org/thread/EOMI5I66ZMKQ2INNFT6T7IAIKUGPZYIE/ or Ubuntu USN-8509-1 at https://ubuntu.com/security/notices/USN-8509-1. As a compensating control for applications that cannot immediately update, independently validate TarInfo.type values returned by the module against expected values before acting on them, rather than trusting the module's normalization output for security-relevant decisions. Alternatively, restrict which archives the application accepts to only internally generated or cryptographically signed archives, eliminating the attacker's ability to supply crafted input - this is the most effective mitigation without a patch but requires application-level changes.

More in Python

View all
CVE-2025-24016 CRITICAL POC
9.9 Feb 10

Wazuh SIEM platform versions 4.4.0 through 4.9.0 contain an unsafe deserialization vulnerability in the DistributedAPI t

CVE-2025-27520 CRITICAL POC
9.8 Apr 04

BentoML version 1.4.2 and earlier contains an unauthenticated remote code execution vulnerability through insecure deser

CVE-2025-2945 CRITICAL POC
9.9 Apr 03

pgAdmin 4 contains critical remote code execution vulnerabilities in the Query Tool download and Cloud Deployment endpoi

CVE-2013-5093 MEDIUM POC
6.8 Sep 27

The renderLocalView function in render/views.py in graphite-web in Graphite 0.9.5 through 0.9.10 uses the pickle Python

CVE-2025-32375 CRITICAL POC
9.8 Apr 09

BentoML is a Python library for building online serving systems optimized for AI apps and model inference. Rated critica

CVE-2014-0224 HIGH POC
7.4 Jun 05

OpenSSL before 0.9.8za, 1.0.0 before 1.0.0m, and 1.0.1 before 1.0.1h does not properly restrict processing of ChangeCiph

CVE-2024-21644 HIGH POC
7.5 Jan 08

pyLoad download manager version prior to 0.5.0b3.dev77 exposes the Flask SECRET_KEY through an unauthenticated endpoint.

CVE-2026-33017 CRITICAL POC
9.3 Mar 17

Langflow (a visual LLM pipeline builder) contains a critical unauthenticated code execution vulnerability (CVE-2026-3301

CVE-2017-9462 HIGH POC
8.8 Jun 06

In Mercurial before 4.1.3, "hg serve --stdio" allows remote authenticated users to launch the Python debugger, and conse

CVE-2026-49869 CRITICAL POC
10.0 Jun 26

Unauthenticated remote code execution affects Kestra OSS (the open-source event-driven orchestration platform) prior to

CVE-2026-39987 CRITICAL POC
9.3 Apr 08

Unauthenticated remote code execution in Marimo ≤0.20.4 allows attackers to execute arbitrary system commands via the `/

CVE-2024-21645 MEDIUM POC
5.3 Jan 08

pyLoad is the free and open-source Download Manager written in pure Python. Rated medium severity (CVSS 5.3), this vulne

Share

CVE-2025-13462 vulnerability details – vuln.today

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy