CVE-2020-12401
Low
No strong exploitation signal.
CVSS base
4.7
MEDIUM
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS — probability of exploitation (30 days)
0.3%
25.6th percentile
CISA KEV
Not listed
Weakness / dates
CWE-203
Published 2020-10-08 · modified 2026-08-19
CVSS breakdown
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
| Attack Vector | L | Local |
| Attack Complexity | H | High |
| Privileges Required | L | Low |
| User Interaction | N | None |
| Scope | U | Unchanged |
| Confidentiality | H | High |
| Integrity | N | None |
| Availability | N | None |
Timeline
- 2020-10-08 — Published (NVD)
- 2026-08-19 — Last modified (NVD)
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
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1631573
- https://lists.debian.org/debian-lts-announce/2023/02/msg00021.html
- https://www.mozilla.org/security/advisories/mfsa2020-36/
- https://www.mozilla.org/security/advisories/mfsa2020-39/
- https://bugzilla.mozilla.org/show_bug.cgi?id=1631573
- https://lists.debian.org/debian-lts-announce/2023/02/msg00021.html
- https://www.mozilla.org/security/advisories/mfsa2020-36/
- https://www.mozilla.org/security/advisories/mfsa2020-39/