CVE-2026-87910tarfile hardlink fallback ignores custom extraction filter rejection via None
- 5.7MediumCVSS base score
- 0.61%Exploitation in 30 daysEPSS · top 50% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
When tarfile extracts a link on a system that doesn't support links, it falls back to extracting a member from the archive. In this case, the filter function is run twice: once for the extracted member, and once with name set to the location of the link. For one of the calls, the return value was ignored. Instead, the member should be skipped if either call returns None.
Timeline
ID reserved
By PSF
- 2 days later
· 2 days later
Published
- 41 days later
· 41 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| PSFCNA (assigner) | 4.0 | Medium5.7 | CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N |
| NVDNVD · Awaiting Analysis | 4.0 | Medium5.7 | CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:A/VC:N/VI:H/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 |
- EPSS (exploitation in 30 days)
- 0.61% · top 50% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.7.
Affected products
Python Software Foundation · CPython
- affected < 3.10.22
- affected 3.11.0 – < 3.11.17
- affected 3.12.0 – < 3.12.15
- affected 3.13.0 – < 3.13.16
- affected 3.14.0 – < 3.14.9
- affected 3.15.0a1 – < 3.15.0rc3
References
References12
- https://mail.python.org/archives/list/[email protected]/thread/57TBTLL2W6APMZR3A25B2YV7GL3EPTDJ/ (opens in a new tab)vendor-advisory
- https://github.com/python/cpython/pull/157266 (opens in a new tab)patch
- https://github.com/python/cpython/issues/157265 (opens in a new tab)issue-tracking
- https://github.com/python/cpython/commit/d9565e54b1fc6d63c5be9afd58114499128fa57b (opens in a new tab)patch
- https://github.com/python/cpython/commit/fb2f0bbc3b35264f09cc2cb2934b7987527a6bc2 (opens in a new tab)patch
- https://github.com/python/cpython/commit/9c17bace90f88dfba6d0e2fe23c8e7ae35f83955 (opens in a new tab)patch
- https://github.com/python/cpython/commit/764fd0af8d9e19d3684a58d2e58bf770f0605036 (opens in a new tab)patch
- https://github.com/python/cpython/commit/2eb0c2f1dc71847731b6ab30aebefd058d482a7f (opens in a new tab)patch
- https://github.com/python/cpython/commit/c1f106d240c4ffcb3608ed0a20e8aba6c865f6d3 (opens in a new tab)patch
- https://github.com/python/cpython/commit/3105a3498aaf681ce128cf5baf83c2e5574267c5 (opens in a new tab)patch
- https://github.com/python/cpython/commit/a4919937a4e1e69a0d178909c6f20557eca5d1d0 (opens in a new tab)patch
- http://www.openwall.com/lists/oss-security/2026/09/11/8 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-76162 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-87910)Record last updated .