High severity · published Jun 23, 2026
CVE-2026-11972
tarfile opened in streaming mode mishandles EOF
8.2
CVSS
0.7%
EPSS
No
On KEV
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 54% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CP
CPython · Python Software Foundation
before 3.10.21; 3.11.0 before 3.11.16; 3.12.0 before 3.12.14; 3.13.0 before 3.13.15; 3.14.0 before 3.14.7; 3.15.0a1 before 3.15.0b4 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-11972
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-11972
github.com
https://github.com/python/cpython/commit/3f031d431f80668e14f3bc066bbf4369cd9281b9
github.com
https://github.com/python/cpython/commit/4ce6bf7c8aa7725828a38981c306f214c1f29365
github.com
https://github.com/python/cpython/commit/7f0dc59c9a70f8f3b4da33d7c4a2ba552a7acc21
github.com
https://github.com/python/cpython/commit/e86666c9dd256d52d0fbef6feb1ea4a51768fdec
github.com
https://github.com/python/cpython/commit/eb63c0f94dfcbea7fda8eab6213818e134d67192
github.com
https://github.com/python/cpython/commit/f50bf13566189c8d0ce5a814f33eff3d89951896
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