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TI-2026-64970 Aliases CVE-2026-100832GHSA-8ffm-wqc4-j2qw

Use after free in Mozilla Firefox

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: 14 fixed, 3 without a fix

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

Summary

Use-after-free in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 140.17, Thunderbird 153.4, Firefox ESR 115.42, and Firefox ESR 140.17.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00245 15th percentileScored 2026-11-07
Fix Partial Firefox (Mozilla): 115.42, 140.17, 153.4Thunderbird (Mozilla): 140.17, 153.4Red Hat: 21 advisoriesRed Hat: 14 fixed, 3 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MozillaFirefox—115.42, 140.17, 153.4Patch availableCNA
MozillaThunderbird—140.17, 153.4Patch availableCNA
  • Firefox VendorMozilla Affected — Fixed in 115.42, 140.17, 153.4 Patch available CNA
  • Thunderbird VendorMozilla Affected — Fixed in 140.17, 153.4 Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*before 115.42.0; 116.0 to before 140.17.0; 141.0 to before 153.4.0VulnerableMozilla
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*before 140.17.0; 141.0 to before 153.4.0VulnerableMozilla
  • cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:* Versions before 115.42.0; 116.0 to before 140.17.0; 141.0 to before 153.4.0 Vulnerable ·Mozilla
  • cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* Versions before 140.17.0; 141.0 to before 153.4.0 Vulnerable ·Mozilla

Remediation

  • Fix · CNA Firefox (Mozilla) Fixed in 115.42, 140.17, 153.4
  • Fix · CNA Thunderbird (Mozilla) Fixed in 140.17, 153.4

Red Hat 21 advisories

  • RHSA-2026:92363 Released 2026-11-02 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux Server (v. 7 ELS) firefox-140.17.0-1.el7_9
  • RHSA-2026:92226 Released 2026-10-29 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) firefox-140.17.0-1.el9_2, firefox-x11-140.17.0-1.el9_2
  • RHSA-2026:92227 Released 2026-10-29 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) firefox-140.17.0-1.el10_0
Show 18 more Red Hat advisories
  • RHSA-2026:92228 Released 2026-10-29 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.6) firefox-140.17.0-1.el8_6
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) firefox-140.17.0-1.el8_6
  • RHSA-2026:92335 Released 2026-10-29 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) firefox-140.17.0-1.el9_6, firefox-x11-140.17.0-1.el9_6
  • RHSA-2026:92327 Released 2026-10-29 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v.8.8) firefox-140.17.0-1.el8_8
    • Red Hat Enterprise Linux AppStream TUS (v.8.8) firefox-140.17.0-1.el8_8
  • RHSA-2026:91633 Released 2026-10-28 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v.8.8) thunderbird-140.17.0-1.el8_8
    • Red Hat Enterprise Linux AppStream TUS (v.8.8) thunderbird-140.17.0-1.el8_8
  • RHSA-2026:92012 Released 2026-10-28 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.4) firefox-140.17.0-1.el9_4, firefox-x11-140.17.0-1.el9_4
  • RHSA-2026:92011 Released 2026-10-28 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) firefox-140.17.0-1.el8_4
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) firefox-140.17.0-1.el8_4
  • RHSA-2026:91634 Released 2026-10-28 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.6) thunderbird-140.17.0-1.el8_6
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) thunderbird-140.17.0-1.el8_6
  • RHSA-2026:90913 Released 2026-10-27 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 8) thunderbird-140.17.0-1.el8_10
  • RHSA-2026:85244 Released 2026-10-19 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) thunderbird-140.17.0-1.el9_6
  • RHSA-2026:85243 Released 2026-10-19 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) thunderbird-140.17.0-1.el8_4
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) thunderbird-140.17.0-1.el8_4
  • RHSA-2026:85241 Released 2026-10-19 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.4) thunderbird-140.17.0-1.el9_4
  • RHSA-2026:85242 Released 2026-10-19 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) thunderbird-140.17.0-1.el9_2
  • RHSA-2026:85240 Released 2026-10-19 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) thunderbird-140.17.0-1.el10_0
  • RHSA-2026:80694 Released 2026-10-12 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 9) thunderbird-140.17.0-1.el9_8
  • RHSA-2026:80674 Released 2026-10-12 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 10) thunderbird-140.17.0-1.el10_2
  • RHSA-2026:76761 Released 2026-10-08 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 9) firefox-140.17.0-1.el9_8, firefox-x11-140.17.0-1.el9_8
  • RHSA-2026:76764 Released 2026-10-06 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 10) firefox-140.17.0-1.el10_2
  • RHSA-2026:76850 Released 2026-10-06 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 8) firefox-140.17.0-1.el8_10

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:76764, RHSA-2026:80674
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2026:76850, RHSA-2026:90913
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:76761, RHSA-2026:80694
Red Hat Enterprise Linux AppStream AUS (v.8.4)Fixed RHSA-2026:85243, RHSA-2026:92011
Red Hat Enterprise Linux AppStream AUS (v.8.6)Fixed RHSA-2026:91634, RHSA-2026:92228
Red Hat Enterprise Linux AppStream E4S (v.8.8)Fixed RHSA-2026:91633, RHSA-2026:92327
Red Hat Enterprise Linux AppStream E4S (v.9.2)Fixed RHSA-2026:85242, RHSA-2026:92226
Red Hat Enterprise Linux AppStream E4S (v.9.4)Fixed RHSA-2026:85241, RHSA-2026:92012
Red Hat Enterprise Linux AppStream EUS (v. 10.0)Fixed RHSA-2026:85240, RHSA-2026:92227
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:85244, RHSA-2026:92335
Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)Fixed RHSA-2026:85243, RHSA-2026:92011
Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)Fixed RHSA-2026:91634, RHSA-2026:92228
Red Hat Enterprise Linux AppStream TUS (v.8.8)Fixed RHSA-2026:91633, RHSA-2026:92327
Red Hat Enterprise Linux Server (v. 7 ELS)Fixed RHSA-2026:92363

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-100832
  2. 2026-10-03 Alias added: GHSA-8ffm-wqc4-j2qw
  3. 2026-10-16 Affected versions changed · Red Hat
  4. 2026-10-16 CVSS score added · Red Hat
  5. 2026-10-24 Fix available: RHSA-2026:76850 · Red Hat
  6. 2026-10-24 Fix available: RHSA-2026:76761 · Red Hat
  7. 2026-10-24 Fix available: RHSA-2026:76764 · Red Hat
  8. 2026-10-24 Fix available: RHSA-2026:80674 · Red Hat
  9. 2026-10-24 Fix available: RHSA-2026:80694 · Red Hat
  10. 2026-10-24 Fix available: RHSA-2026:85240 · Red Hat
  11. 2026-10-24 Fix available: RHSA-2026:85243 · Red Hat
  12. 2026-10-24 Fix available: RHSA-2026:85241 · Red Hat
  13. 2026-10-24 Fix available: RHSA-2026:85244 · Red Hat
  14. 2026-10-24 Fix available: RHSA-2026:85242 · Red Hat
  15. 2026-10-24 Fix available: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux AppStream (v. 8), Red Hat Enterprise Linux AppStream (v. 9) +6 · Red Hat
  16. 2026-10-28 Affected versions changed · Red Hat
  17. 2026-10-29 Fix available: RHSA-2026:90913 · Red Hat
  18. 2026-10-29 Fix available: RHSA-2026:92335 · Red Hat
  19. 2026-10-29 Fix available: RHSA-2026:92327 · Red Hat
  20. 2026-10-29 Fix available: Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream TUS (v.8.8) · Red Hat
  21. 2026-10-30 Fix available: RHSA-2026:91634 · Red Hat
  22. 2026-10-30 Fix available: RHSA-2026:91633 · Red Hat
  23. 2026-10-30 Fix available: RHSA-2026:92012 · Red Hat
  24. 2026-10-30 Fix available: RHSA-2026:92011 · Red Hat
  25. 2026-10-30 Fix available: RHSA-2026:92227 · Red Hat
  26. 2026-10-30 Fix available: RHSA-2026:92226 · Red Hat
  27. 2026-10-30 Fix available: RHSA-2026:92228 · Red Hat
  28. 2026-10-30 Fix available: Red Hat Enterprise Linux AppStream AUS (v.8.6), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) · Red Hat
  29. 2026-11-02 Fix available: Red Hat Enterprise Linux Server (v. 7 ELS) · Red Hat
  30. 2026-11-03 Fix available: RHSA-2026:92363 · Red Hat

References

Advisory 5

Other 1

  • TI-2024-08981 Use after free in Mozilla Firefox KEVCVSS 3.1CRITICAL 9.8
  • TI-2022-09832 Use after free in Mozilla Firefox KEVCVSS 3.1CRITICAL 9.6
  • TI-2019-08769 Improper input validation in Mozilla Firefox ESR KEVCVSS 3.1CRITICAL 10.0
  • TI-2010-03577 Mozilla Firefox 3.5.x through 3.5.14 and 3.6.x through 3.6.11, Thunderbird 3.1.6 before… KEVCVSS 3.1CRITICAL 9.8
  • TI-2023-04799 Out-of-bounds write in Google Chrome KEVCVSS 3.1HIGH 8.8
  • TI-2023-04477 Out-of-bounds write in Google Chrome KEVCVSS 3.1HIGH 8.8
See all 3444 →

Sources

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