CVE-2025-27607

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

HIGH
8.8
CVSS Score
Published: March 7, 2025 at 04:18 PM UTC
Updated: June 17, 2026 at 09:03 AM UTC
1 product affected across 1 vendorPython JSON Logger

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Severity
HIGH8.8
Exploit prediction
EPSS 2%
SSVC
PoC

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

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 3.3.0
Affected range stops below 3.3.0, so it looks safe — our inference, not a vendor statement

SSVC — Action Prioritization

SSVCPoCNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.8HIGHGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-829NVD-CWE-noinfo

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