Vulnerability in Nhairs Python-Json-Logger

CVE-2025-27607

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.

EPSS: 0.015 (72.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-27607?
CVE-2025-27607 is a high-severity vulnerability in Nhairs Python-Json-Logger, classified under Inclusion of Functionality from Untrusted Control Sphere. CVSS score: 8.8/10. Published 2025-03-07.
How severe is CVE-2025-27607?
High severity. CVSS v3 base score is 8.8 out of 10.
Is CVE-2025-27607 known to be exploited?
4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.