Vulnerability · Published Mar 7, 2025 · Assigned by GitHub_M

CVE-2025-27607Python JSON Logger has a Potential RCE via missing `msgspec-python313-pre` dependency

High 8.8

In plain English

A high-severity security flaw in python-json-logger from nhairs. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 1.6% (higher than 76% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code.

Severity (CVSS 3.1)8.8High
Exploit odds (30 days)1.6%top 24.0% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack tooling1Public PoC

Official description

Python JSON Logger is a JSON Formatter for Python Logging. Between 30 December 2024 and 4 March 2025 Python JSON Logger was vulnerable to RCE through a missing dependency. This occurred because msgspec-python313-pre was deleted by the owner leaving the name open to being claimed by a third party. If the package was claimed, it would allow them RCE on any Python JSON Logger user who installed the development dependencies on Python 3.13 (e.g. pip install python-json-logger[dev]). This issue has been resolved with 3.3.0.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Ubuntu:22.04:LTSpython-pythonjsonloggerno fix listedUBUNTU-CVE-2025-27607
Ubuntu:24.04:LTSpython-pythonjsonloggerno fix listedUBUNTU-CVE-2025-27607
Ubuntu:25.10python-pythonjsonloggerno fix listedUBUNTU-CVE-2025-27607
Ubuntu:26.04:LTSpython-pythonjsonloggerno fix listedUBUNTU-CVE-2025-27607
Ubuntu:26.10python-pythonjsonloggerno fix listedUBUNTU-CVE-2025-27607

Affected products (as reported)

VendorProductVersions
nhairs python-json-logger >= 3.2.0, < 3.3.0

Weakness: CWE-829 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

References