Vulnerability · CVE-2025-4516
There is an issue in CPython when using .
Published May 15, 2025 · corrected/updated Jul 31, 2026 · Python Software Foundation CPython · evidence confidence high
There is an issue in CPython when using . 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.
Grounded briefings
Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.
Executive
CVE-2025-4516 is a medium public vulnerability record for Python Software Foundation CPython. It is not currently listed in the CISA Known Exploited catalog. Check the linked vendor or CERT advisories for patch status. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.
System administrator
Identify whether Python Software Foundation CPython is in your estate, then compare installed versions with the affected ranges. Affected packages or ranges on record: Python Software Foundation CPython 3.13.0 <3.13.4 (3.13.0 <3.13.4). Check the linked vendor or CERT advisories for patch status. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.
Security analyst
Signals on file: CVSS 5.9, EPSS 23.0%. It is not currently listed in the CISA Known Exploited catalog. Sources contributing to this record: cve_org, euvd. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.
Exploitation and remediation
Exploitation evidence
Not listed as known exploited in CISA KEV. Not in CISA KEV or VulnCheck KEV.
Patch and remediation
No required-action text is stored yet. Use the vendor or CERT links in Sources for patch availability.
Safe detection guidance
Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
May 15, 2025 · EUVD
Detected
There is an issue in CPython when using . 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.
Jul 31, 2026 · EUVD
Updated
There is an issue in CPython when using . 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.
Affected
- vendor Python Software Foundation CPython 3.13.0 <3.13.43.13.0 <3.13.4
Sources
- CVE.orgVulnerability recordCVE-2025-4516
Official CVE identifier
cve.org - EUVDVulnerability recordEUVD-2025-15156
There is an issue in CPython when using . 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 Decod
euvd.enisa.europa.eu