CVE-2026-11972
tarfile opened in streaming mode mishandles EOF
Description
When using the "tarfile" module with a file opened in "streaming mode" (mode="r|") the tarfile module did not properly handle EOF, making archive parsing take exponentially longer.
INFO
Published Date :
June 23, 2026, 11:16 p.m.
Last Modified :
June 30, 2026, 4:16 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-11972
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 | HIGH | 28c92f92-d60d-412d-b760-e73465c3df22 | ||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update Python interpreter to a patched version.
- Avoid using tarfile in streaming mode.
- Review tarfile usage for potential infinite loops.
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-2026-11972.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-11972 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-2026-11972
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-2026-11972 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-11972 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]
Jun. 30, 2026
Action Type Old Value New Value Added Reference https://github.com/python/cpython/commit/3f031d431f80668e14f3bc066bbf4369cd9281b9 Added Reference https://github.com/python/cpython/commit/4ce6bf7c8aa7725828a38981c306f214c1f29365 Added Reference https://github.com/python/cpython/commit/7f0dc59c9a70f8f3b4da33d7c4a2ba552a7acc21 Added Reference https://github.com/python/cpython/commit/e86666c9dd256d52d0fbef6feb1ea4a51768fdec Added Reference https://github.com/python/cpython/commit/eb63c0f94dfcbea7fda8eab6213818e134d67192 Added Reference https://github.com/python/cpython/commit/f50bf13566189c8d0ce5a814f33eff3d89951896 Changed Affected [{'repo': 'https://github.com/python/cpython', 'vendor': 'Python Software Foundation', 'modules': ['tarfile'], 'product': 'CPython', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '3.16.0', 'versionType': 'python'}], 'defaultStatus': 'unaffected'}] [{'repo': 'https://github.com/python/cpython', 'vendor': 'Python Software Foundation', 'modules': ['tarfile'], 'product': 'CPython', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '3.15.0', 'versionType': 'python'}], 'defaultStatus': 'unaffected'}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 24, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-11972', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-06-24T15:33:49.665045Z'} -
CVE Modified by [email protected]
Jun. 24, 2026
Action Type Old Value New Value Changed Affected [{'repo': 'https://github.com/python/cpython', 'vendor': 'Python Software Foundation', 'modules': ['tarfile'], 'product': 'CPython', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '3.15.0', 'versionType': 'python'}], 'defaultStatus': 'unaffected'}] [{'repo': 'https://github.com/python/cpython', 'vendor': 'Python Software Foundation', 'modules': ['tarfile'], 'product': 'CPython', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '3.16.0', 'versionType': 'python'}], 'defaultStatus': 'unaffected'}] Changed Description When using the "tarfile" module with a file opened in "streaming mode" (mode="r|") the tarfile module did not properly handle EOF, meaning an archive could be parsed in an infinite loop. When using the "tarfile" module with a file opened in "streaming mode" (mode="r|") the tarfile module did not properly handle EOF, making archive parsing take exponentially longer. Removed Reference https://github.com/python/cpython/commit/3f031d431f80668e14f3bc066bbf4369cd9281b9 Removed Reference https://github.com/python/cpython/commit/4ce6bf7c8aa7725828a38981c306f214c1f29365 Removed Reference https://github.com/python/cpython/commit/e86666c9dd256d52d0fbef6feb1ea4a51768fdec Removed Reference https://github.com/python/cpython/commit/f50bf13566189c8d0ce5a814f33eff3d89951896 -
CVE Modified by [email protected]
Jun. 24, 2026
Action Type Old Value New Value Added Reference https://github.com/python/cpython/commit/3f031d431f80668e14f3bc066bbf4369cd9281b9 Added Reference https://github.com/python/cpython/commit/4ce6bf7c8aa7725828a38981c306f214c1f29365 Added Reference https://github.com/python/cpython/commit/e86666c9dd256d52d0fbef6feb1ea4a51768fdec Added Reference https://github.com/python/cpython/commit/f50bf13566189c8d0ce5a814f33eff3d89951896 Changed Affected [{'repo': 'https://github.com/python/cpython', 'vendor': 'Python Software Foundation', 'modules': ['tarfile'], 'product': 'CPython', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '3.16.0', 'versionType': 'python'}], 'defaultStatus': 'unaffected'}] [{'repo': 'https://github.com/python/cpython', 'vendor': 'Python Software Foundation', 'modules': ['tarfile'], 'product': 'CPython', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '3.15.0', 'versionType': 'python'}], 'defaultStatus': 'unaffected'}] -
New CVE Received by [email protected]
Jun. 23, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://github.com/python/cpython', 'vendor': 'Python Software Foundation', 'modules': ['tarfile'], 'product': 'CPython', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '3.16.0', 'versionType': 'python'}], 'defaultStatus': 'unaffected'}] Added Description When using the "tarfile" module with a file opened in "streaming mode" (mode="r|") the tarfile module did not properly handle EOF, meaning an archive could be parsed in an infinite loop. Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/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-252 Added CWE CWE-606 Added CWE CWE-770 Added Reference https://github.com/python/cpython/issues/151981 Added Reference https://github.com/python/cpython/pull/151982 Added Reference https://mail.python.org/archives/list/[email protected]/thread/AXPSKKTSRKXTTJULW3XSIC74WZNAAPPB/