CVE-2020-26972: mozilla firefox Use After Free
Vulnerability summary
CVE-2020-26972 is a critical (CVSS 9.8) Use After Free vulnerability in mozilla firefox. EPSS estimates a 1.31% chance of exploitation in the next 30 days, higher than 70.2% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 3 · Related 3Timeline
- 07-01-2021PublishedVulnerability first disclosed.
- 04-08-2024Last modifiedVulnerability information updated.
Description
The lifecycle of IPC Actors allows managed actors to outlive their manager actors; and the former must ensure that they are not attempting to use a dead actor they have a reference to. Such a check was omitted in WebGL, resulting in a use-after-free and a potentially exploitable crash. This vulnerability affects Firefox < 84.
CVSS metrics
3 scores · 2 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
1.31%
Chance of exploitation in the next 30 days
Percentile
70%
Versus all other CVEs
30-day change
+0.02 pp
From 1.29% on 20-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Ubuntu5 products
- firefox< 84.0+build3-0ubuntu0.16.04.1 | < 84.0+build3-0ubuntu0.18.04.1 | < 84.0+build3-0ubuntu0.20.04.1
- mozjs38All versions (No fix recorded)
- mozjs52All versions (No fix recorded)
- mozjs68All versions (No fix recorded)
- mozjs78All versions (No fix recorded)
Mozilla1 product
- firefox≥ unspecified, < 84 | < 84.0
2 vendors · 6 products