Medium severity · published Mar 4, 2026
CVE-2026-2297
SourcelessFileLoader does not use io.open_code()
5.7
CVSS
0.2%
EPSS
No
On KEV
Description
The import hook in CPython that handles legacy *.pyc files (SourcelessFileLoader) is incorrectly handled in FileLoader (a base class) and so does not use io.open_code() to read the .pyc files. sys.audit handlers for this audit event therefore do not fire.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 11% 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 3.13.13; 3.14.0 before 3.14.4; 3.15.0a1 before 3.15.0a7 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-2297
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-2297
github.com
https://github.com/python/cpython/commit/482d6f8bdba9da3725d272e8bb4a2d25fb6a603e
github.com
https://github.com/python/cpython/commit/69ddd9bb2cc4bd69b1565647c18659c6a789ccd9
github.com
https://github.com/python/cpython/commit/876858c9f65d9ab656c7fa639f268ce7856d89dd
github.com
https://github.com/python/cpython/commit/a51b1b512de1d56b3714b65628a2eae2b07e535e
github.com
https://github.com/python/cpython/commit/c70adad78caeeea33f92f560ecb93331ca11bf66
github.com
https://github.com/python/cpython/commit/e58e9802b9bec5cdbf48fc9bf1da5f4fda482e86
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