CVE-2020-12395: canonical ubuntu_linux Out-of-bounds Write
Vulnerability summary
CVE-2020-12395 is a high (CVSS 10.0) Out-of-bounds Write vulnerability in canonical ubuntu_linux. EPSS estimates a 2.60% chance of exploitation in the next 30 days, higher than 85.1% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 27 · Related 11Timeline
- 26-05-2020PublishedVulnerability first disclosed.
- 04-08-2024Last modifiedVulnerability information updated.
Description
Mozilla developers and community members reported memory safety bugs present in Firefox 75 and Firefox ESR 68.7. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox ESR < 68.8, Firefox < 76, and Thunderbird < 68.8.0.
CVSS metrics
4 scores · 3 sources · 2 versions- OSV · DebianEcosystem advisory · calculated9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- NVDNIST9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
2.60%
Chance of exploitation in the next 30 days
Percentile
85%
Versus all other CVEs
30-day change
+0.34 pp
From 2.26% on 19-09-2026
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< 76.0+build2-0ubuntu0.16.04.1 | < 76.0+build2-0ubuntu0.18.04.1 | < 76.0+build2-0ubuntu0.20.04.1
- mozjs38All versions (No fix recorded)
- mozjs52All versions (No fix recorded)
- mozjs68All versions (No fix recorded)
- thunderbird< 1:68.8.0+build2-0ubuntu0.16.04.2 | < 1:68.8.0+build2-0ubuntu0.18.04.2 | < 1:68.8.0+build2-0ubuntu0.20.04.2
Mozilla3 products
- firefox≥ unspecified, < 76 | < 76.0
- firefox_esr≥ unspecified, < 68.8 | < 68.8.0
- thunderbird≥ unspecified, < 68.8.0 | < 68.8.0
Debian2 products
- firefox-esr< 68.8.0esr-1
- thunderbird< 1:68.8.0-1
Canonical1 product
- ubuntu_linuxEOL16.04 | 18.04 | 19.10 | 20.04
4 vendors · 11 products
