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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2025-4516 Detail

Description

There is an issue in CPython when using `bytes.decode("unicode_escape", error="ignore|replace")`. If you are not using the "unicode_escape" encoding or an error handler your usage is not affected. To work-around this issue you may stop using the error= handler and instead wrap the bytes.decode() call in a try-except catching the DecodeError.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  Python Software Foundation
CVSS-B 5.9 MEDIUM
Vector:  CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
http://www.openwall.com/lists/oss-security/2025/05/16/4 CVE
http://www.openwall.com/lists/oss-security/2025/05/19/1 CVE
https://github.com/python/cpython/commit/4398b788ffc1f954a2c552da285477d42a571292 Python Software Foundation
https://github.com/python/cpython/commit/6279eb8c076d89d3739a6edb393e43c7929b429d Python Software Foundation
https://github.com/python/cpython/commit/69b4387f78f413e8c47572a85b3478c47eba8142 Python Software Foundation
https://github.com/python/cpython/commit/73b3040f592436385007918887b7e2132aa8431f Python Software Foundation
https://github.com/python/cpython/commit/8d35fd1b34935221aff23a1ab69a429dd156be77 Python Software Foundation
https://github.com/python/cpython/commit/9f69a58623bd01349a18ba0c7a9cb1dad6a51e8e Python Software Foundation
https://github.com/python/cpython/commit/ab9893c40609935e0d40a6d2a7307ea51aec598b Python Software Foundation
https://github.com/python/cpython/issues/133767 Python Software Foundation
https://github.com/python/cpython/pull/129648 Python Software Foundation
https://mail.python.org/archives/list/[email protected]/thread/L75IPBBTSCYEF56I2M4KIW353BB3AY74/ Python Software Foundation

Weakness Enumeration

CWE-ID CWE Name Source
CWE-416 Use After Free Python Software Foundation  

Change History

4 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-4516
NVD Published Date:
05/15/2025
NVD Last Modified:
06/03/2025
Source:
Python Software Foundation