CVE-2026-15310
zipfile: bzip2/LZMA/Zstandard members decompress without a max_length bound, defeating chunked-read memory limits
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.
INFO
Published Date :
Aug. 25, 2026, 3:16 p.m.
Last Modified :
Sept. 4, 2026, 1:17 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-15310
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 4.0 | LOW | 28c92f92-d60d-412d-b760-e73465c3df22 | ||||
| CVSS 4.0 | LOW | [email protected] |
Solution
- Update Python to the latest version.
- Apply security patches from the vendor.
- Review memory allocation code for zip files.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-15310.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-15310 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-15310
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-15310 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-15310 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
Sep. 04, 2026
Action Type Old Value New Value Added Reference https://github.com/python/cpython/commit/31980e84b9a708424a0a1dfecde3fc991e313f89 -
CVE Modified by [email protected]
Sep. 02, 2026
Action Type Old Value New Value Added Affected Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/15xxx/CVE-2026-15310.json">CVE-2026-15310</a> -
CVE Modified by [email protected]
Sep. 01, 2026
Action Type Old Value New Value Added Reference https://github.com/python/cpython/commit/1b424c0178a01e155fd0267dc28a8fc1159b33a8 -
CVE Modified by [email protected]
Aug. 26, 2026
Action Type Old Value New Value Added Affected Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/15xxx/CVE-2026-15310.json">CVE-2026-15310</a> Added Reference https://github.com/python/cpython/commit/f897dbf2f36a5935700b7c2d94d4681d2136b7d4 Added Reference https://github.com/python/cpython/issues/156002 Added Reference https://github.com/python/cpython/pull/156003 Added Reference https://mail.python.org/archives/list/[email protected]/thread/YUHXURX2WZGKGNA4ANYBQS2VZRYQ5JNK/ Removed Reference https://github.com/python/cpython/issues/156002 Removed Reference https://github.com/python/cpython/pull/156003 Removed Reference https://mail.python.org/archives/list/[email protected]/thread/YUHXURX2WZGKGNA4ANYBQS2VZRYQ5JNK/ -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Aug. 25, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-15310', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-08-25T15:34:06.442859Z'} -
New CVE Received by [email protected]
Aug. 25, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://github.com/python/cpython', 'vendor': 'Python Software Foundation', 'product': 'CPython', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '3.16.0', 'versionType': 'python'}], 'defaultStatus': 'unaffected'}] Added 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. Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:L/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 Added CWE CWE-400 Added Reference https://github.com/python/cpython/issues/156002 Added Reference https://github.com/python/cpython/pull/156003 Added Reference https://mail.python.org/archives/list/[email protected]/thread/YUHXURX2WZGKGNA4ANYBQS2VZRYQ5JNK/