CVE-2010-4237
Mercurial Improper Certificate Validation vulnerability
Mercurial before 1.6.4 fails to verify the Common Name field of SSL certificates which allows remote attackers who acquire a certificate signed by a Certificate Authority to perform a man-in-the-middle attack.
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
- None
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
5.9
Mercurial before 1.6.4 fails to verify the Common Name field of SSL certificates which allows remote attackers who acquire a certificate signed by a Certificate Authority to perform a man-in-the-middle attack.
- Record
CVE-2010-4237- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - CVSS 2.0
- 4.3 Medium
AV:N/AC:M/Au:N/C:N/I:P/A:N - Weakness
- CWE-295
- Updated
- 2026-11-02
CVE List No score
Mercurial before 1.6.4 fails to verify the Common Name field of SSL certificates which allows remote attackers who acquire a certificate signed by a Certificate Authority to perform a man-in-the-middle attack.
- Record
CVE-2010-4237- Updated
- 2026-11-02
EUVDEUVD-2022-1665 No score
Mercurial before 1.6.4 fails to verify the Common Name field of SSL certificates which allows remote attackers who acquire a certificate signed by a Certificate Authority to perform a man-in-the-middle attack.
- Record
EUVD-2022-1665- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-7gf7-7wx4-mxmw
5.9
Mercurial Improper Certificate Validation vulnerability
Mercurial before 1.6.4 fails to verify the Common Name field of SSL certificates which allows remote attackers who acquire a certificate signed by a Certificate Authority to perform a man-in-the-middle attack.
- Record
GHSA-7gf7-7wx4-mxmw- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-295
- Updated
- 2026-11-02
OSV
5.9
Mercurial before 1.6.4 fails to verify the Common Name field of SSL certificates which allows remote attackers who acquire a certificate signed by a Certificate Authority to perform a man-in-the-middle attack.
- Record
CVE-2010-4237- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
OSVDEBIAN-CVE-2010-4237
5.9
Mercurial before 1.6.4 fails to verify the Common Name field of SSL certificates which allows remote attackers who acquire a certificate signed by a Certificate Authority to perform a man-in-the-middle attack.
- Record
DEBIAN-CVE-2010-4237- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
OSVGHSA-7gf7-7wx4-mxmw
5.9
Mercurial Improper Certificate Validation vulnerability
Mercurial before 1.6.4 fails to verify the Common Name field of SSL certificates which allows remote attackers who acquire a certificate signed by a Certificate Authority to perform a man-in-the-middle attack.
- Record
GHSA-7gf7-7wx4-mxmw- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-295
- Updated
- 2026-11-02
OSVPYSEC-2026-665
5.9
Mercurial Improper Certificate Validation vulnerability
Mercurial before 1.6.4 fails to verify the Common Name field of SSL certificates which allows remote attackers who acquire a certificate signed by a Certificate Authority to perform a man-in-the-middle attack.
- Record
PYSEC-2026-665- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
mercurialPyPI |
before 1.6.4 | 1.6.4 |
mercurialDebian:12 |
before 1.6.4-1 | 1.6.4-1 |
mercurialDebian:13 |
before 1.6.4-1 | 1.6.4-1 |
mercurialDebian:14 |
before 1.6.4-1 | 1.6.4-1 |
mercurialPyPI |
before 1.6.4, plus listed versions 0.8.10.90.9.10.9.20.9.3 Show 25 moreShow less0.9.40.9.51.01.0.11.0.21.11.1.11.1.21.21.2.11.31.3.11.41.4.11.4.21.4.31.51.5.11.5.21.5.31.5.41.61.6.11.6.21.6.3 |
1.6.4 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, products | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2010-4237 is a medium vulnerability (CVSS 5.9) in Mercurial, published October 29, 2019. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.82%, the 57th percentile. Fixed in mercurial 1.6.4.