jenkinsci/jenkins · Security
Non-constant time HMAC comparison
- GHSA ID
- GHSA-fj6f-6933-839j
- CVE ID
- CVE-2020-2102
- Severity
- medium
- Published
- Updated
- CVSS
- 5.3 · CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
- CVSS v3
- 5.3 · CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
Description
Jenkins 2.218 and earlier, LTS 2.204.1 and earlier does not use a constant-time comparison when checking whether two HMACs are equal. This could potentially allow attackers to use statistical methods to obtain a valid HMAC for an attacker-controlled input value.
Jenkins 2.219, LTS 2.204.2 now uses a constant-time comparison when validating HMACs.
CWEs
- CWE-203 · Observable Discrepancy
- CWE-208 · Observable Timing Discrepancy
References
- https://nvd.nist.gov/vuln/detail/CVE-2020-2102 ↗
- https://access.redhat.com/errata/RHBA-2020:0402 ↗
- https://access.redhat.com/errata/RHBA-2020:0675 ↗
- https://access.redhat.com/errata/RHSA-2020:0681 ↗
- https://access.redhat.com/errata/RHSA-2020:0683 ↗
- https://jenkins.io/security/advisory/2020-01-29/#SECURITY-1660 ↗
- http://www.openwall.com/lists/oss-security/2020/01/29/1 ↗
- https://github.com/jenkinsci/jenkins/commit/6f35dbb939ebe947bdb1979010b208480f1d0e31 ↗
- https://github.com/advisories/GHSA-fj6f-6933-839j ↗