CVE-2025-4516

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/python/cpython/commit/4398b788ffc1f954a2c552da285477d42a571292
https://github.com/python/cpython/commit/6279eb8c076d89d3739a6edb393e43c7929b429d
https://github.com/python/cpython/commit/69b4387f78f413e8c47572a85b3478c47eba8142
https://github.com/python/cpython/commit/73b3040f592436385007918887b7e2132aa8431f
https://github.com/python/cpython/commit/8d35fd1b34935221aff23a1ab69a429dd156be77
https://github.com/python/cpython/commit/9f69a58623bd01349a18ba0c7a9cb1dad6a51e8e
https://github.com/python/cpython/commit/ab9893c40609935e0d40a6d2a7307ea51aec598b
https://github.com/python/cpython/issues/133767
https://github.com/python/cpython/pull/129648
https://mail.python.org/archives/list/security-announce@python.org/thread/L75IPBBTSCYEF56I2M4KIW353BB3AY74/
http://www.openwall.com/lists/oss-security/2025/05/16/4
http://www.openwall.com/lists/oss-security/2025/05/19/1

Configurations

No configuration.

History

03 Jun 2025, 14:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-05-15 14:15

Updated : 2025-06-03 14:15

NVD link : CVE-2025-4516

Mitre link : CVE-2025-4516

CVE.ORG link : CVE-2025-4516

JSON object : View

Products Affected

No product.

CWE

CWE-416

Use After Free

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