CVE-2025-4516CWE-416

CVE-2025-4516

published May 15, 2025

CVSS
5.9
EPSS
0%
Percentile
12.5
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS
5.9 · NONE
CVSS v4.0
Not supplied
EPSS
0.00225 · 12.5th percentile
Weakness
CWE-416 · Use After Free
Published
2025-05-15T18:15Z
References (12)
https://github.com/python/cpython/commit/4398b788ffc1f954a2c552da285477d42a571292 · [email protected]https://github.com/python/cpython/commit/6279eb8c076d89d3739a6edb393e43c7929b429d · [email protected]https://github.com/python/cpython/commit/69b4387f78f413e8c47572a85b3478c47eba8142 · [email protected]https://github.com/python/cpython/commit/73b3040f592436385007918887b7e2132aa8431f · [email protected]https://github.com/python/cpython/commit/8d35fd1b34935221aff23a1ab69a429dd156be77 · [email protected]https://github.com/python/cpython/commit/9f69a58623bd01349a18ba0c7a9cb1dad6a51e8e · [email protected]https://github.com/python/cpython/commit/ab9893c40609935e0d40a6d2a7307ea51aec598b · [email protected]https://github.com/python/cpython/issues/133767 · [email protected]https://github.com/python/cpython/pull/129648 · [email protected]https://mail.python.org/archives/list/[email protected]/thread/L75IPBBTSCYEF56I2M4KIW353BB3AY74/ · [email protected]http://www.openwall.com/lists/oss-security/2025/05/16/4 · af854a3a-2127-422b-91ae-364da2661108http://www.openwall.com/lists/oss-security/2025/05/19/1 · af854a3a-2127-422b-91ae-364da2661108
EPSS history
Timeline
  • 15 MAY 13:29Z
    Use-after-free in "unicode_escape" decoder with error handler
    cvelistv5