GHSA-hq85-5cpj-mr62
uv's bundled CA store trusts an emSign root whose intermediate CA keys are compromised
GHSA-hq85-5cpj-mr62 is a critical vulnerability (CVSS 9.1) in uv, published October 20, 2026. No source lists public exploit code. Fixed in uv 0.13.4.
- Severity
- 9.1 CriticalCVSS 4.0, GitHub Advisories
- Exploit chance
- UnscoredNo EPSS score yet
- Exploitation
- None knownNot on CISA’s or ENISA’s lists
- Fixed in
0.13.4uv +2 more
Description
By default, uv verifies TLS connections against a vendored copy of the webpki-root-certs bundle. Versions before 0.13.4 include the emSign ECC Root CA - G3 root. Eight eMudhra intermediate CA certificates that chain to that root have compromised private keys, and the CA has revoked them.
An attacker with one of the compromised keys can issue certificates that uv accepts for any hostname, and can be used to issue certificates to enable MITM attacks.
uv 0.13.4 removes the root from its vendored bundle, following webpki-root-certs 1.0.10. Upgrade to 0.13.4 or later.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Affected packages
| Package | Affected | Fixed |
|---|---|---|
uvPyPI | before 0.13.4 | 0.13.4 |
uvPyPI | before 0.13.4, plus listed versions 0.0.50.1.00.1.10.1.100.1.11 Show 45 moreShow less0.1.120.1.130.1.140.1.150.1.160.1.170.1.180.1.190.1.20.1.200.1.210.1.220.1.230.1.240.1.250.1.260.1.270.1.280.1.290.1.30.1.300.1.310.1.320.1.330.1.340.1.350.1.360.1.370.1.380.1.390.1.40.1.400.1.410.1.420.1.430.1.440.1.450.1.50.1.60.1.70.1.80.1.90.10.00.10.10.10.10 | 0.13.4 |
uvRoot:PyPI | before 0.12.15+aikido.1 | 0.12.15+aikido.10.12.23+aikido.10.12.21+aikido.10.11.28+aikido.10.13.2+aikido.10.12.19+aikido.10.13.1+aikido.10.12.22+aikido.10.12.17+aikido.10.12.18+aikido.10.13.3+aikido.10.9.28+aikido.1 |
What each source reports
GitHub Advisories Score used
uv's bundled CA store trusts an emSign root whose intermediate CA keys are compromised
By default, uv verifies TLS connections against a vendored copy of the webpki-root-certs bundle. Versions before 0.13.4 include the emSign ECC Root CA - G3 root. Eight eMudhra intermediate CA certificates that chain to that root have compromised private keys, and the CA has revoked them.
An attacker with one of the compromised keys can issue certificates that uv accepts for any hostname, and can be used to issue certificates to enable MITM attacks.
uv 0.13.4 removes the root from its vendored bundle, following webpki-root-certs 1.0.10. Upgrade to 0.13.4 or later.
- Record
GHSA-hq85-5cpj-mr62- CVSS 4.0
- 9.1 Critical
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-295
- Updated
- 2026-11-02
OSV
uv's bundled CA store trusts an emSign root whose intermediate CA keys are compromised
By default, uv verifies TLS connections against a vendored copy of the webpki-root-certs bundle. Versions before 0.13.4 include the emSign ECC Root CA - G3 root. Eight eMudhra intermediate CA certificates that chain to that root have compromised private keys, and the CA has revoked them.
An attacker with one of the compromised keys can issue certificates that uv accepts for any hostname, and can be used to issue certificates to enable MITM attacks.
uv 0.13.4 removes the root from its vendored bundle, following webpki-root-certs 1.0.10. Upgrade to 0.13.4 or later.
- Record
GHSA-hq85-5cpj-mr62- CVSS 4.0
- 9.1 Critical
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-295
- Updated
- 2026-11-02
OSVPYSEC-2026-4321
uv's bundled CA store trusts an emSign root whose intermediate CA keys are compromised
By default, uv verifies TLS connections against a vendored copy of the webpki-root-certs bundle. Versions before 0.13.4 include the emSign ECC Root CA - G3 root. Eight eMudhra intermediate CA certificates that chain to that root have compromised private keys, and the CA has revoked them.
An attacker with one of the compromised keys can issue certificates that uv accepts for any hostname, and can be used to issue certificates to enable MITM attacks.
uv 0.13.4 removes the root from its vendored bundle, following webpki-root-certs 1.0.10. Upgrade to 0.13.4 or later.
- Record
PYSEC-2026-4321- CVSS 4.0
- 9.1 Critical
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N - Updated
- 2026-11-02
OSVROOT-APP-PYPI-GHSA-hq85-5cpj-mr62No score
GHSA-hq85-5cpj-mr62 in uv - Patched by Root
Root has patched GHSA-hq85-5cpj-mr62 in the uv package for Root:PyPI. Multiple fixed versions available.
- Record
ROOT-APP-PYPI-GHSA-hq85-5cpj-mr62- Updated
- 2026-11-02
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | GitHub Advisories, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
References
github.com/astral-sh/uv/security/advisories/GHSA-hq85-5cpj-mr62
emudhra.we-have-a-problem.com
groups.google.com/a/mozilla.org/g/dev-security-policy/c/0R3XLJL6FuE/m/0XofdebrAAAJ
pypi.org/project/uv
Left out here: 277 versions. The JSON record has them.