CVE-2026-11940: Python Software Foundation CPython · Path Traversal
Affects Python Software Foundation CPythonSource CVE Database V5
Mentioned vulnerabilities
Not known to be exploited · CVSS 7.8 High · fixed in 3.15.0b4 : patch Python Software Foundation CPython soon.
Data as of 5 Nov 2026, 23:24 UTC
- EPSS
- 0.7% chance of exploitation in 30 days – higher than 55% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 3.15.0b4, 3.14.7, 3.13.15 +3
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 23 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 6 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Python Software FoundationCPython | Affected
| Fixed in
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| Python Software FoundationCPython | Affected
| Fixed in
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| Python Software FoundationCPython | Affected
| Fixed in
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| Python Software FoundationCPython | Affected
| Fixed in
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| Python Software FoundationCPython | Affected
| Fixed in
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| Python Software FoundationCPython | Affected
| Fixed in
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Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
If you cannot patch yet, avoid extracting untrusted tar archives using tarfile.extractall() or apply manual validation of archive contents to prevent directory traversal via symlinks and hardlinks.
Description
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.
References
- github.com/python/cpython/pull/151559 (opens in a new tab)
- mail.python.org/archives/list/security-announce@python.org/thread/LD6QIISNQFQYOIEPJNEUIPV7S3V76FZH/ (opens in a new tab)
- github.com/python/cpython/issues/151558 (opens in a new tab)
- github.com/python/cpython/commit/27dd970bf6b17ebca7c8ed486a40ab043ed7af8f (opens in a new tab)
- github.com/python/cpython/commit/672825e2f36a57e173959b0d9d409d4560dab8df (opens in a new tab)
- github.com/python/cpython/commit/771d12dda5140313db0ac550292987975651bbde (opens in a new tab)
- github.com/python/cpython/commit/79c06bd5c6afa3c440d50faf7ee1b147c8832b4c (opens in a new tab)
- github.com/python/cpython/commit/be13e86f6b9788a6f4d0419dffef72cbae5865c9 (opens in a new tab)
- github.com/python/cpython/commit/e5fdbd8d5aa923bd9111b112ea73bd6ec7c47877 (opens in a new tab)
- github.com/python/cpython/commit/0f852b3f07dd8e71e40326a51c02afbf16a42cc5 (opens in a new tab)