CVE-2025-27607Public exploitNetwork attack vector

Code execution via unclaimed development dependency

Published Mar 7, 2025 · Updated Mar 7, 2025

Dependency confusion in nhairs Python JSON Logger 3.2.0 through 3.2.1 allows attackers to execute code during a development install. The dev extra in pyproject.toml conditionally names the deleted msgspec-python313-pre distribution for Python 3.13, so pip resolves and executes a third party's package during installation. Exploitation requires installation of the dev extra under Python 3.13; PyPI has blocked the dependency name, and no malicious package execution was reported.

CVSS severity8.8
High
EPSS probability1.58%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Dependency confusion in nhairs Python JSON Logger 3.2.0 through 3.2.1 allows attackers to execute code during a development install. The dev extra in pyproject.toml conditionally names the deleted msgspec-python313-pre distribution for Python 3.13, so pip resolves and executes a third party's package during installation. Exploitation requires installation of the dev extra under Python 3.13; PyPI has blocked the dependency name, and no malicious package execution was reported.

The record

CVE
CVE-2025-27607
Published
Mar 7, 2025
Updated
Mar 7, 2025
Vendor
nhairs
Product
Python JSON Logger
Classifications
CWE-829, T1195.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 7, 2025CVE publishedPublication date reported by the CVE source.
  2. Mar 7, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 3.2.0, < 3.3.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

nhairs · Python JSON Loggerversion=>= 3.2.0, < 3.3.0

Published CVSS scores

8.8GitHub CNACVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-829Inclusion of Functionality from Untrusted Control Sphere
T1195.001Compromise Software Dependencies

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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