CVE-2025-4565
python-protobuf: Unbounded recursion in Python Protobuf
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · June 16, 2025
Updated · August 21, 2026
Description
A flaw was found in the python protobuf package which can result in a denial of service. Applications that parse untrusted Protocol Buffers data containing an arbitrary number of recursive groups, recursive messages, or a series of SGROUP tags can be corrupted by exceeding the Python recursion limit. This can result in a Denial of service by crashing the application that integrates the package with a RecursionError.
Statement
The availability impact of this denial-of-service vulnerability is confined to applications that directly integrate the Protobuf package. Within the context of a Red Hat system, the host machine itself is not expected to be impacted, thereby limiting the scope of disruption to individual application instances rather than broader system instability.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
CVSS / CWE
CVSS 3.1 · 5.3CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CWE-674 · Uncontrolled Recursion