SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2025-27607

Between 30 December 2024 and 4 March 2025 Python JSON Logger was vulnerable to RCE through a missing dependency.

HIGH 8.8EPSS 1.99%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.99%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1
8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
1.99% probability · 80th percentile
CISA KEV
Not listed
Weakness
CWE-829
Affected
nhairs/python json logger
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.