Loading
Loading
We use strictly necessary cookies to run this site, and analytics cookies to understand how it's used. See our Privacy Policy for details.
A GitHub-reviewed security advisory, not necessarily under active exploitation the way our CISA KEV advisories are, but a real, disclosed vulnerability in an open-source dependency.
Affected packages
Vulnerable: >= 2019.03.09, < 2026.10.19
Patched in 2026.10.19
Details
Certifi versions before 2026.10.18 include the emSign ECC Root CA - G3 root certificate in their bundled CA store. Eight eMudhra intermediate CA certificates that chain to this root have compromised private keys and the CA has revoked them.
An attacker with one of the compromised keys can issue valid-looking certificates for any hostname. If the attacker is also on-path, they can intercept or modify TLS traffic from clients that trust the certifi bundle. Examples include requests, urllib3 and pip, and the Python.org macOS installer.
Certifi 2026.10.18 removed all emSign roots from the bundle. Certifi 2026.10.19 restored the emSign roots that are not affected. Upgrade to 2026.10.19 or later, and rebuild container images that vendor certifi.
Talk to us about this
Find out whether this dependency (or others like it) is actually reachable in your codebase.
Get help patching, or building dependency-scanning into your pipeline going forward.
A secure code review or supply chain review finds this before an advisory does.