PyPI: uv

GHSA-hq85-5cpj-mr62

Safety vulnerability ID: SFTY-20261020-91055

Affected versions of the uv package are vulnerable to Improper Certificate Validation due to a compromised root certificate being included in its vendored trust store. The bundled `webpki-root-certs` copy used for TLS verification trusts the `emSign ECC Root CA - G3` root, under which eight eMudhra intermediate CA certificates with compromised private keys were issued and later revoked, yet uv continues to accept certificates chaining to this root by default. An attacker in possession of one of the compromised intermediate keys can forge valid-looking TLS certificates for arbitrary hostnames and perform man-in-the-middle attacks against uv's network connections, intercepting or tampering with package downloads and other HTTPS traffic.

Created at: Oct 20, 2026Updated at: Oct 20, 2026

Overview

uv's bundled CA store trusts an emSign root whose intermediate CA keys are compromised

Advisory

uv – Improper Certificate Validation

Affected Package

Affecting uv package, versions< 0.13.4

Also affects

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How to Fix

Upgradeuvto0.13.4or higher.

Mitigation and Workarounds

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Vulnerable Functions

Functions linked to known vulnerabilities.

Vulnerable function data is available for Enterprise customers

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Safety

Verified by Safety

Our Cybersecurity Intelligence Team reviewed this vulnerability. We combine public data with our own research to find issues not yet reported to public sources.

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