CVE-2026-15310
zipfile: bzip2/LZMA/Zstandard members decompress without a max_length bound, defeating chunked-read memory limits
- State
- Published
- Severity
- 2.1 Low
- Published
- Aug 25, 2026
- Updated
- Oct 2, 2026
- Reserved
- Jul 9, 2026
Description
When decompressing crafted zip files using the bzip/LZMA/Zstandard
compressions, Python could use an attacker-controlled size to
pre-allocate memory, possibly resulting in memory exhaustion.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 2.1 Low | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N | PSF |
Weaknesses
Affected Products
| Product | Versions |
|---|---|
CPythonPython Software Foundation |
|
References
- https://github.com/python/cpython/pull/156003patch
- https://github.com/python/cpython/issues/156002issue-tracking
- https://mail.python.org/archives/list/security-announce@python.org/thread/YUHXURX2WZGKGNA4ANYBQS2VZRYQ5JNK/vendor-advisory
- https://github.com/python/cpython/commit/f897dbf2f36a5935700b7c2d94d4681d2136b7d4patch
- https://github.com/python/cpython/commit/1b424c0178a01e155fd0267dc28a8fc1159b33a8patch
- https://github.com/python/cpython/commit/31980e84b9a708424a0a1dfecde3fc991e313f89patch
- https://github.com/python/cpython/commit/e2311cfb3dd518f008f312fe0631f4f7490d237apatch
- https://github.com/python/cpython/commit/f507e6946a3194e83e1d7b8ee6e14567175e46depatch
- https://github.com/python/cpython/commit/9d167992b59cf5e23c66b9ed742b13f5925f7d70patch
- https://github.com/python/cpython/commit/dcdd406ddbfc4cb29b24c3df17cbabe21d316ce1patch
- https://github.com/python/cpython/commit/09a2e7e6678b4f65449e7ad8f112c48f944591e2patch
- https://github.com/python/cpython/commit/6257029de42ef89b67f3d20137de87d43e197530patch
- https://github.com/python/cpython/commit/c2bfbcdd1a11690507a10bc0998f95b8dc6b6facpatch
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