Vulnerability in Mozilla Firefox
CVE-2020-12402
During RSA key generation, bignum implementations used a variation of the Binary Extended Euclidean Algorithm which entailed significantly input-dependent flow. This allowed an attacker able to perform electromagnetic-based side channel attacks to record traces leading to the recovery of the secret primes. *Note:* An unmodified Firefox browser does not generate RSA keys in normal operation and is not affected, but products built on top of it might. This vulnerability affects Firefox < 78.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.4 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.003 (24.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 25th percentile — 24.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- Mozilla Firefox — versions unspecified
- Debian Linux — versions 9.0
- Fedoraproject Fedora — versions 32
- openSUSE Leap — versions 15.1, 15.2
Weakness classification (CWE)
Public proof-of-concept exploits
References
- www.mozilla.org/security/advisories/mfsa2020-24/ (Vendor Advisory)
- bugzilla.mozilla.org/show_bug.cgi (Permissions Required, Issue Tracking, Vendor Advisory)
- lists.opensuse.org/opensuse-security-announce/2020-07/msg00016.html (vendor-advisory, Third Party Advisory)
- lists.opensuse.org/opensuse-security-announce/2020-07/msg00018.html (vendor-advisory, Third Party Advisory)
- usn.ubuntu.com/4417-1/ (vendor-advisory, Third Party Advisory)
- lists.opensuse.org/opensuse-security-announce/2020-07/msg00027.html (vendor-advisory, Third Party Advisory)
- www.debian.org/security/2020/dsa-4726 (vendor-advisory, Third Party Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.opensuse.org/opensuse-security-announce/2020-07/msg00049.html (vendor-advisory, Third Party Advisory)
- security.gentoo.org/glsa/202007-10 (vendor-advisory, Third Party Advisory)
Frequently asked questions
- What is CVE-2020-12402?
- CVE-2020-12402 is a medium-severity vulnerability in Mozilla Firefox, classified under Observable Discrepancy. CVSS score: 4.4/10. Published 2020-07-09.
- How severe is CVE-2020-12402?
- Medium severity. CVSS v3 base score is 4.4 out of 10.
- Is CVE-2020-12402 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.