Cyber Posture

CVE-2025-27607

HighPublic PoC

Published: 07 March 2025

Published
07 March 2025
Modified
01 July 2025
KEV Added
Patch
CVSS Score 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.2176 95.8th percentile
Risk Priority 31 60% EPSS · 20% KEV · 20% CVSS

Description

Adversaries may manipulate software dependencies and development tools prior to receipt by a final consumer for the purpose of data or system compromise.

Security Summary

CVE-2025-27607 is a remote code execution (RCE) vulnerability in Python JSON Logger, a JSON formatter for Python's logging module. The issue arose between December 30, 2024, and March 4, 2025, due to a missing dependency called msgspec-python313-pre, which was deleted by its owner and left available for claiming by a third party. Users installing development dependencies for Python JSON Logger on Python 3.13, such as via the command "pip install python-json-logger[dev]", were at risk of pulling in a malicious package under that name.

An attacker with no privileges could exploit this by claiming the abandoned package name on the Python Package Index (PyPI) and publishing malicious code. Exploitation requires user interaction, specifically installing the affected development dependencies during the vulnerability window on Python 3.13, after which the attacker achieves RCE with high impacts on confidentiality, integrity, and availability (CVSS 8.8; AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

The vulnerability has been resolved in Python JSON Logger version 3.3.0. GitHub security advisory GHSA-wmxh-pxcx-9w24 and related commits detail the fix, which addresses the dependency issue. Practitioners should upgrade to 3.3.0 or later and review dependency installation practices, particularly for development extras.

Details

CWE(s)
CWE-829NVD-CWE-noinfo

Affected Products

nhairs
python json logger
≤ 3.3.0

MITRE ATT&CK Enterprise Techniques

T1195.001 Compromise Software Dependencies and Development Tools Initial Access
Adversaries may manipulate software dependencies and development tools prior to receipt by a final consumer for the purpose of data or system compromise.
Why these techniques?

The CVE describes a supply chain attack where an attacker reclaims an abandoned dependency package name on PyPI and publishes malicious code, which is pulled in during 'pip install python-json-logger[dev]' on Python 3.13, directly enabling RCE. This maps to T1195.001: Compromise Software Dependencies and Development Tools.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

References