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TI-2026-13672 Aliases CVE-2026-16365GHSA-534q-w7ff-7vh6

Improper privilege management in Mozilla Firefox

Priority MEDIUM 40CWE-269Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Privilege escalation, Security bypass
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-269 and CWE-284.

Summary

Privilege escalation in the DOM: Workers component. This vulnerability was fixed in Firefox 153, Thunderbird 153, Firefox ESR 140.15, and Thunderbird 140.15.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00278 20th percentileScored 2026-11-07
Fix Partial Firefox (Mozilla): 140.15, 153Thunderbird (Mozilla): 140.15, 153Red 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—140.15, 153Patch availableCNA
MozillaThunderbird—140.15, 153Patch availableCNA
  • Firefox VendorMozilla Affected — Fixed in 140.15, 153 Patch available CNA
  • Thunderbird VendorMozilla Affected — Fixed in 140.15, 153 Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*before 153.0.0VulnerableMozilla
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*before 153.0VulnerableMozilla
  • cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:* Versions before 153.0.0 Vulnerable ·Mozilla
  • cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* Versions before 153.0 Vulnerable ·Mozilla

Remediation

  • Fix · CNA Firefox (Mozilla) Fixed in 140.15, 153
  • Fix · CNA Thunderbird (Mozilla) Fixed in 140.15, 153

Red Hat 21 advisories

  • RHSA-2026:82122 Released 2026-10-13 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) thunderbird-140.16.0-1.el8_4
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) thunderbird-140.16.0-1.el8_4
  • RHSA-2026:81912 Released 2026-10-13 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v.8.8) thunderbird-140.16.0-1.el8_8
    • Red Hat Enterprise Linux AppStream TUS (v.8.8) thunderbird-140.16.0-1.el8_8
  • RHSA-2026:81913 Released 2026-10-13 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.6) thunderbird-140.16.0-1.el8_6
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) thunderbird-140.16.0-1.el8_6
Show 18 more Red Hat advisories
  • RHSA-2026:80503 Released 2026-10-12 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) thunderbird-140.15.0-1.el9_6
  • RHSA-2026:77632 Released 2026-10-08 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) thunderbird-140.15.0-1.el9_2
  • RHSA-2026:77627 Released 2026-10-08 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.4) thunderbird-140.15.0-1.el9_4
  • RHSA-2026:77631 Released 2026-10-08 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) thunderbird-140.15.0-1.el10_0
  • RHSA-2026:77610 Released 2026-10-07 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) firefox-140.15.0-1.el10_0
  • RHSA-2026:76895 Released 2026-10-06 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) firefox-140.15.0-1.el9_6, firefox-x11-140.15.0-1.el9_6
  • RHSA-2026:76894 Released 2026-10-06 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) firefox-140.15.0-1.el8_4
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) firefox-140.15.0-1.el8_4
  • RHSA-2026:76742 Released 2026-10-06 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) firefox-140.15.0-1.el9_2, firefox-x11-140.15.0-1.el9_2
  • RHSA-2026:76740 Released 2026-10-06 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.4) firefox-140.15.0-1.el9_4, firefox-x11-140.15.0-1.el9_4
  • RHSA-2026:76741 Released 2026-10-06 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux Server (v. 7 ELS) firefox-140.15.0-1.el7_9
  • RHSA-2026:76745 Released 2026-10-06 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.6) firefox-140.15.0-1.el8_6
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) firefox-140.15.0-1.el8_6
  • RHSA-2026:76746 Released 2026-10-06 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v.8.8) firefox-140.15.0-1.el8_8
    • Red Hat Enterprise Linux AppStream TUS (v.8.8) firefox-140.15.0-1.el8_8
  • RHSA-2026:73971 Released 2026-09-30 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 8) thunderbird-140.16.0-1.el8_10
  • RHSA-2026:73130 Released 2026-09-29 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 10) thunderbird-140.16.0-1.el10_2
  • RHSA-2026:70642 Released 2026-09-24 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 9) thunderbird-140.16.0-1.el9_8
  • RHSA-2026:68549 Released 2026-09-17 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 8) firefox-140.15.0-1.el8_10
  • RHSA-2026:67133 Released 2026-09-14 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 9) firefox-140.15.0-1.el9_8, firefox-x11-140.15.0-1.el9_8
  • RHSA-2026:67129 Released 2026-09-14 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 10) firefox-140.15.0-1.el10_2

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-2026:67129, RHSA-2026:73130
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2026:68549, RHSA-2026:73971
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:67133, RHSA-2026:70642
Red Hat Enterprise Linux AppStream AUS (v.8.4)Fixed RHSA-2026:76894, RHSA-2026:82122
Red Hat Enterprise Linux AppStream AUS (v.8.6)Fixed RHSA-2026:76745, RHSA-2026:81913
Red Hat Enterprise Linux AppStream E4S (v.8.8)Fixed RHSA-2026:76746, RHSA-2026:81912
Red Hat Enterprise Linux AppStream E4S (v.9.2)Fixed RHSA-2026:76742, RHSA-2026:77632
Red Hat Enterprise Linux AppStream E4S (v.9.4)Fixed RHSA-2026:76740, RHSA-2026:77627
Red Hat Enterprise Linux AppStream EUS (v. 10.0)Fixed RHSA-2026:77610, RHSA-2026:77631
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:76895, RHSA-2026:80503
Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)Fixed RHSA-2026:76894, RHSA-2026:82122
Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)Fixed RHSA-2026:76745, RHSA-2026:81913
Red Hat Enterprise Linux AppStream TUS (v.8.8)Fixed RHSA-2026:76746, RHSA-2026:81912
Red Hat Enterprise Linux Server (v. 7 ELS)Fixed RHSA-2026:76741

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-16365
  2. 2026-10-03 Alias added: GHSA-534q-w7ff-7vh6
  3. 2026-10-06 Fix available: RHSA-2026:76741 · Red Hat
  4. 2026-10-06 Fix available: RHSA-2026:76740 · Red Hat
  5. 2026-10-06 Fix available: RHSA-2026:76746 · Red Hat
  6. 2026-10-06 Fix available: RHSA-2026:76742 · Red Hat
  7. 2026-10-06 Fix available: Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream E4S (v.9.2), Red Hat Enterprise Linux AppStream E4S (v.9.4) +2 · Red Hat
  8. 2026-10-07 Fix available: RHSA-2026:76745 · Red Hat
  9. 2026-10-07 Fix available: RHSA-2026:76894 · Red Hat
  10. 2026-10-07 Fix available: RHSA-2026:76895 · Red Hat
  11. 2026-10-07 Fix available: Red Hat Enterprise Linux AppStream AUS (v.8.4), Red Hat Enterprise Linux AppStream AUS (v.8.6), Red Hat Enterprise Linux AppStream EUS (v.9.6) +2 · Red Hat
  12. 2026-10-07 Fix available: RHSA-2026:77610 · Red Hat
  13. 2026-10-07 Fix available: Red Hat Enterprise Linux AppStream EUS (v. 10.0) · Red Hat
  14. 2026-10-08 Affected versions changed · Red Hat
  15. 2026-10-09 Fix available: RHSA-2026:77631 · Red Hat
  16. 2026-10-09 Fix available: RHSA-2026:77627 · Red Hat
  17. 2026-10-09 Fix available: RHSA-2026:77632 · Red Hat
  18. 2026-10-12 Fix available: RHSA-2026:80503 · Red Hat
  19. 2026-10-12 Affected versions changed · Red Hat
  20. 2026-10-13 Fix available: RHSA-2026:81912 · Red Hat
  21. 2026-10-13 Fix available: RHSA-2026:81913 · Red Hat
  22. 2026-10-13 Affected versions changed · Red Hat
  23. 2026-10-14 Fix available: RHSA-2026:82122 · Red Hat

References

Advisory 2

Other 3

  • 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