CVE-2026-15310: CWE-400 in Python Software Foundation CPython
Description
CVE-2026-15310 is a low-severity vulnerability in CPython where decompressing specially crafted zip files using bzip, LZMA, or Zstandard compression methods can lead to memory exhaustion. This occurs because Python may use an attacker-controlled size to pre-allocate memory during decompression. The vulnerability affects multiple CPython versions prior to specific patch releases. No known exploits are reported in the wild, and no patch information is provided in the input data.
CVSS v4.0
Score 2.1low
Affected software
Python Software Foundation
CPython
pkg:github/CPythonRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-15310) in the Python Software Foundation's CPython implementation involves improper handling of decompression of zip files compressed with bzip, LZMA, or Zstandard algorithms. An attacker can craft a zip file that specifies a size used by Python to pre-allocate memory, potentially causing memory exhaustion (CWE-400). The issue affects multiple CPython versions before certain fixed releases. The CVSS 4.0 score is 2.1, indicating low severity. There is no information about available patches or vendor advisories in the provided data.
Potential Impact
The impact is limited to potential memory exhaustion during decompression of maliciously crafted zip files, which could lead to denial of service by exhausting system memory resources. There is no indication of code execution, data corruption, or privilege escalation. No known exploits are reported in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is confirmed, avoid decompressing untrusted zip files compressed with bzip, LZMA, or Zstandard in affected CPython versions to mitigate potential memory exhaustion.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- PSF
- Date Reserved
- 2026-07-09T17:39:12.652Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6a8db46cacd9273b495e7a1e
Added to database: 08/25/2026, 15:27:40 UTC
Last enriched: 10/07/2026, 21:05:55 UTC
Last updated: 10/10/2026, 18:48:17 UTC
Views: 88
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