Description
During ECDSA signature generation, padding applied in the nonce designed to ensure constant-time scalar multiplication was removed, resulting in variable-time execution dependent on secret data. This vulnerability affects Firefox < 80 and Firefox for Android < 80.
Affected products
mozilla: firefox; mozilla: firefox mobile
References8
- bugzilla.mozilla.org/show_bug.cgi?id=1631573 Issue TrackingPermissions RequiredVendor Advisory
- www.mozilla.org/security/advisories/mfsa2020-36/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2020-39/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=1631573 Issue TrackingPermissions RequiredVendor Advisory
- www.mozilla.org/security/advisories/mfsa2020-36/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2020-39/ Vendor Advisory
- lists.debian.org/debian-lts-announce/2023/02/msg00021.html
- lists.debian.org/debian-lts-announce/2023/02/msg00021.html
Metrics
- CVSS 3.1
-
4.7
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 0% percentile: 26 · as of 11 November 2026
- CWE
- CWE-203
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