CVE-2026-11972

tarfile opened in streaming mode mishandles EOF

Published Jun 23, 2026 CVSS 4.0 · 8.2 High EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Weaknesses CWE-835
References
Metrics threat_severity

None

cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H'}

threat_severity

Moderate

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values 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. 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.
References
Type Values Removed Values Added
First Time appeared Python
Python cpython
Vendors & Products Python
Python cpython
Type Values Removed Values 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.
Title tarfile opened in streaming mode mishandles EOF
Weaknesses CWE-252
CWE-606
CWE-770
References
Metrics cvssV4_0

{'score': 8.2, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'}

Sources

Status
PUBLISHED
Assigner
PSF
Published
Updated
Aug 13, 2026, 12:28 AM
Reserved
Jun 11, 2026, 11:35 AM
Status
Awaiting Analysis
Published
Jun 23, 2026, 11:16 PM
Modified
Oct 25, 2026, 11:10 PM
Severity
Moderate
Public date
Jun 23, 2026, 10:02 PM