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/69b4387f78f413e8c47572a85b3478c47eba8142
https://github.com/python/cpython/commit/9f69a58623bd01349a18ba0c7a9cb1dad6a51e8e
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

19 May 2025, 10:15

Type	Values Removed	Values Added
References		() http://www.openwall.com/lists/oss-security/2025/05/19/1 -

16 May 2025, 18:16

Type	Values Removed	Values Added
References		() http://www.openwall.com/lists/oss-security/2025/05/16/4 -

16 May 2025, 14:43

Type	Values Removed	Values Added
Summary		(es) Hay un problema en CPython al usar `bytes.decode("unicode_escape", error="ignore\|replace")`. Si no usa la codificación "unicode_escape" ni un controlador de errores, su uso no se ve afectado. Para solucionar este problema, puede dejar de usar el controlador `error=` y, en su lugar, encapsular la llamada `bytes.decode()` en un `try-except` que capture el `DecodeError`.

15 May 2025, 14:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-05-15 14:15

Updated : 2025-05-19 10:15

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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