CVE-2026-87910
tarfile hardlink fallback ignores custom extraction filter rejection via None
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.
INFO
Published Date :
Sept. 11, 2026, 6:16 p.m.
Last Modified :
Sept. 22, 2026, 1:16 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-87910
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 | MEDIUM | 28c92f92-d60d-412d-b760-e73465c3df22 | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update the tarfile library to the latest version.
- Review archive extraction logic for link handling.
- Ensure filter return values are always checked.
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-2026-87910.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-87910 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-2026-87910
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-2026-87910 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-87910 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. 22, 2026
Action Type Old Value New Value Added Reference https://github.com/python/cpython/commit/9c17bace90f88dfba6d0e2fe23c8e7ae35f83955 -
CVE Modified by [email protected]
Sep. 12, 2026
Action Type Old Value New Value Added Affected Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/87xxx/CVE-2026-87910.json">CVE-2026-87910</a> Added Reference https://github.com/python/cpython/commit/d9565e54b1fc6d63c5be9afd58114499128fa57b Added Reference https://github.com/python/cpython/commit/fb2f0bbc3b35264f09cc2cb2934b7987527a6bc2 -
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Sep. 11, 2026
Action Type Old Value New Value Added Reference http://www.openwall.com/lists/oss-security/2026/09/11/8 -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Sep. 11, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-87910', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-09-11T19:23:39.973519Z'} -
New CVE Received by [email protected]
Sep. 11, 2026
Action Type Old Value New Value Added 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. Added CVSS V4.0 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 Added CWE CWE-22 Added CWE CWE-59 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/87xxx/CVE-2026-87910.json">CVE-2026-87910</a> Added Reference https://github.com/python/cpython/issues/157265 Added Reference https://github.com/python/cpython/pull/157266 Added Reference https://mail.python.org/archives/list/[email protected]/thread/57TBTLL2W6APMZR3A25B2YV7GL3EPTDJ/