CVE-2026-11940
highpriority · track · 0EPSS 0.007 · 54 %ileDEEUUSEPSS · scored 2026-10-22
tarfile.extractall() with the 'data' or 'tar' filter could be bypassed by a crafted archive where a hardlink references a symlink stored at a deeper name than the hardlink itself. The extraction fallback validated the symlink at it's archived location but recreated it at the hardlink's shallower path, letting a relative target the filter judged contained escape the destination directory. This allowed a malicious tar archive to create a symlink pointing outside the destination, enabling out-of-destination file reads or writes. This was an incomplete fix of CVE-2025-4330.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.7–7.8
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (30)
Products and version ranges known to be affected.
advisories (6)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-2044CPython: Mehrere SchwachstellenDeutsch2026-06-23csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in CPython ausnutzen, um Dateien zu manipulieren, Sicherheitsmaßnahmen zu umgehen oder vertrauliche Informationen offenzulegen.
- WID-SEC-W-2026-3595IBM QRadar SIEM: Mehrere SchwachstellenDeutsch2026-09-27csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in IBM QRadar SIEM ausnutzen, um beliebigen Programmcode auszuführen, um seine Privilegien zu erhöhen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, um Dateien zu manipulieren, um einen Cross-Site Scripting Angriff durchzuführen und um Sicherheitsvorkehrungen zu umgehen.
- BIT-libpython-2026-11940tarfile extraction filter bypass allows escaping the destination directory2026-07-30vendor · osvUS
tarfile.extractall() with the 'data' or 'tar' filter could be bypassed by a crafted archive where a hardlink references a symlink stored at a deeper name than the hardlink itself. The extraction fallback validated the symlink at it's archived location but recreated it at the hardlink's shallower path, letting a relative target the filter judged contained escape the destination directory. This allowed a malicious tar archive to create a symlink pointing outside the destination, enabling out-of-destination file reads or writes. This was an incomplete fix of CVE-2025-4330.
- BIT-python-2026-11940tarfile extraction filter bypass allows escaping the destination directory2026-07-30vendor · osvUS
tarfile.extractall() with the 'data' or 'tar' filter could be bypassed by a crafted archive where a hardlink references a symlink stored at a deeper name than the hardlink itself. The extraction fallback validated the symlink at it's archived location but recreated it at the hardlink's shallower path, letting a relative target the filter judged contained escape the destination directory. This allowed a malicious tar archive to create a symlink pointing outside the destination, enabling out-of-destination file reads or writes. This was an incomplete fix of CVE-2025-4330.
- BIT-python-min-2026-11940tarfile extraction filter bypass allows escaping the destination directory2026-07-30vendor · osvUS
tarfile.extractall() with the 'data' or 'tar' filter could be bypassed by a crafted archive where a hardlink references a symlink stored at a deeper name than the hardlink itself. The extraction fallback validated the symlink at it's archived location but recreated it at the hardlink's shallower path, letting a relative target the filter judged contained escape the destination directory. This allowed a malicious tar archive to create a symlink pointing outside the destination, enabling out-of-destination file reads or writes. This was an incomplete fix of CVE-2025-4330.
- PSF-2026-302026-06-23vendor · osvUS
tarfile.extractall() with the 'data' or 'tar' filter could be bypassed by a crafted archive where a hardlink references a symlink stored at a deeper name than the hardlink itself. The extraction fallback validated the symlink at it's archived location but recreated it at the hardlink's shallower path, letting a relative target the filter judged contained escape the destination directory. This allowed a malicious tar archive to create a symlink pointing outside the destination, enabling out-of-destination file reads or writes. This was an incomplete fix of CVE-2025-4330.
also known as (7)
Other names and identifiers for this entity.
- CNNVD-2026-98645985cnnvd
- EUVD-2026-38490enisa_euvd
- GHSA-9mc4-rqmq-h467enisa_euvd
- BIT-libpython-2026-11940osv
- BIT-python-2026-11940osv
- BIT-python-min-2026-11940osv
- PSF-2026-30osv
sources
Which sources assert this record, and when.
references (28)
External citations — patches, advisories, analysis.
- https://github.com/python/cpython/commit/27dd970bf6b17ebca7c8ed486a40ab043ed7af8fcnnvd
- https://github.com/python/cpython/commit/672825e2f36a57e173959b0d9d409d4560dab8dfcnnvd
- https://github.com/python/cpython/commit/771d12dda5140313db0ac550292987975651bbdecnnvd
- https://github.com/python/cpython/commit/79c06bd5c6afa3c440d50faf7ee1b147c8832b4ccnnvd
- https://github.com/python/cpython/issues/151558cnnvd
- https://github.com/python/cpython/pull/151559cnnvd
- https://mail.python.org/archives/list/security-announce@python.org/thread/LD6QIISNQFQYOIEPJNEUIPV7S3V76FZH/cnnvd
- https://www.python.org/Patchcnnvd
Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.
Free scan