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TI-2020-12344 Aliases CVE-2020-15669GHSA-8vqh-gxqj-vj4q

Use after free in Mozilla Firefox ESR

Priority MEDIUM 40CWE-416Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 16 fixed, 1 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.

Summary

When aborting an operation, such as a fetch, an abort signal may be deleted while alerting the objects to be notified. This results in a use-after-free and we presume that with enough effort it could have been exploited to run arbitrary code. This vulnerability affects Firefox ESR < 68.12 and Thunderbird < 68.12.

Why it matters now

EPSS 0.01119 66th percentileScored 2026-11-07
Fix Partial Firefox ESR (Mozilla): 68.12Thunderbird (Mozilla): 68.12Red Hat: 10 advisoriesRed Hat: 16 fixed, 1 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
MozillaFirefox ESRbefore 68.1268.12Patch availableCNA
MozillaThunderbirdbefore 68.1268.12Patch availableCNA
  • Firefox ESR VendorMozilla Affected before 68.12 Fixed in 68.12 Patch available CNA
  • Thunderbird VendorMozilla Affected before 68.12 Fixed in 68.12 Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*before 68.12VulnerableMozilla
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*before 68.12VulnerableMozilla
  • cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:* Versions before 68.12 Vulnerable ·Mozilla
  • cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* Versions before 68.12 Vulnerable ·Mozilla

Remediation

  • Fix · CNA Firefox ESR (Mozilla) Fixed in 68.12
  • Fix · CNA Thunderbird (Mozilla) Fixed in 68.12

Red Hat 10 advisories

  • RHSA-2020:3643 Released 2020-09-08 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux Desktop (v. 6) thunderbird-68.12.0-1.el6_10
    • Red Hat Enterprise Linux Server Optional (v. 6) thunderbird-68.12.0-1.el6_10
    • Red Hat Enterprise Linux Workstation (v. 6) thunderbird-68.12.0-1.el6_10
  • RHSA-2020:3634 Released 2020-09-07 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 8) thunderbird-68.12.0-1.el8_2
  • RHSA-2020:3632 Released 2020-09-07 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v. 8.1) thunderbird-68.12.0-1.el8_1
Show 7 more Red Hat advisories
  • RHSA-2020:3633 Released 2020-09-07 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v. 8.0) thunderbird-68.12.0-1.el8_0
  • RHSA-2020:3631 Released 2020-09-07 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux Client (v. 7) thunderbird-68.12.0-1.el7_8
    • Red Hat Enterprise Linux Server Optional (v. 7) thunderbird-68.12.0-1.el7_8
    • Red Hat Enterprise Linux Workstation (v. 7) thunderbird-68.12.0-1.el7_8
  • RHSA-2020:3559 Released 2020-08-26 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream EUS (v. 8.1) firefox-78.2.0-3.el8_1
  • RHSA-2020:3557 Released 2020-08-26 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 8) firefox-78.2.0-2.el8_2
  • RHSA-2020:3556 Released 2020-08-26 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux Client (v. 7) firefox-68.12.0-1.el7_8
    • Red Hat Enterprise Linux Client Optional (v. 7) firefox-68.12.0-1.el7_8
    • Red Hat Enterprise Linux Server (v. 7) firefox-68.12.0-1.el7_8
    • Red Hat Enterprise Linux Server Optional (v. 7) firefox-68.12.0-1.el7_8
    • Red Hat Enterprise Linux Workstation (v. 7) firefox-68.12.0-1.el7_8
    • Red Hat Enterprise Linux Workstation Optional (v. 7) firefox-68.12.0-1.el7_8
  • RHSA-2020:3558 Released 2020-08-26 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux Desktop (v. 6) firefox-68.12.0-1.el6_10
    • Red Hat Enterprise Linux Desktop Optional (v. 6) firefox-68.12.0-1.el6_10
    • Red Hat Enterprise Linux HPC Node Optional (v. 6) firefox-68.12.0-1.el6_10
    • Red Hat Enterprise Linux Server (v. 6) firefox-68.12.0-1.el6_10
    • Red Hat Enterprise Linux Server Optional (v. 6) firefox-68.12.0-1.el6_10
    • Red Hat Enterprise Linux Workstation (v. 6) firefox-68.12.0-1.el6_10
    • Red Hat Enterprise Linux Workstation Optional (v. 6) firefox-68.12.0-1.el6_10
  • RHSA-2020:3555 Released 2020-08-26 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v. 8.0) firefox-78.2.0-3.el8_0

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 5AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2020:3557, RHSA-2020:3634
Red Hat Enterprise Linux AppStream E4S (v. 8.0)Fixed RHSA-2020:3555, RHSA-2020:3633
Red Hat Enterprise Linux AppStream EUS (v. 8.1)Fixed RHSA-2020:3559, RHSA-2020:3632
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2020:3556, RHSA-2020:3631
Red Hat Enterprise Linux Client Optional (v. 7)Fixed RHSA-2020:3556
Red Hat Enterprise Linux Desktop (v. 6)Fixed RHSA-2020:3558, RHSA-2020:3643
Red Hat Enterprise Linux Desktop Optional (v. 6)Fixed RHSA-2020:3558
Red Hat Enterprise Linux HPC Node Optional (v. 6)Fixed RHSA-2020:3558
Red Hat Enterprise Linux Server (v. 6)Fixed RHSA-2020:3558
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2020:3556
Red Hat Enterprise Linux Server Optional (v. 6)Fixed RHSA-2020:3558, RHSA-2020:3643
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2020:3556, RHSA-2020:3631
Red Hat Enterprise Linux Workstation (v. 6)Fixed RHSA-2020:3558, RHSA-2020:3643
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2020:3556, RHSA-2020:3631
Red Hat Enterprise Linux Workstation Optional (v. 6)Fixed RHSA-2020:3558
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2020:3556

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-15669
  2. 2026-10-03 Alias added: GHSA-8vqh-gxqj-vj4q

References

Advisory 3

  • TI-2022-15364 Use after free in Mozilla Firefox CVSS 3.1CRITICAL 9.8
  • TI-2022-13633 Out-of-bounds write in Mozilla Thunderbird CVSS 3.1CRITICAL 9.8
  • TI-2021-03015 XML injection in Mozilla Firefox ESR CVSS 3.1CRITICAL 10.0
  • TI-2022-09755 Protection mechanism failure in Mozilla Firefox CVSS 3.1CRITICAL 9.6
  • TI-2022-07009 Protection mechanism failure in Mozilla Firefox CVSS 3.1CRITICAL 9.6
  • TI-2023-18834 Use after free in Mozilla Firefox CVSS 3.1HIGH 8.8
See all 486 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences