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TI-2026-13686 Aliases CVE-2026-16379GHSA-wh9f-q55j-mp9r

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
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.

Summary

Privilege escalation in the DOM: Content Processes component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.

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): 140.13, 153Thunderbird (Mozilla): 140.13, 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—140.13, 153Patch availableCNA
MozillaThunderbird—140.13, 153Patch availableCNA
  • Firefox VendorMozilla Affected — Fixed in 140.13, 153 Patch available CNA
  • Thunderbird VendorMozilla Affected — Fixed in 140.13, 153 Patch available CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*before 140.13.0VulnerableMozilla
cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*before 153.0.0VulnerableMozilla
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*before 140.13.0; 141.0 to before 153.0VulnerableMozilla
  • cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:* Versions before 140.13.0 Vulnerable ·Mozilla
  • cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:* Versions before 153.0.0 Vulnerable ·Mozilla
  • cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* Versions before 140.13.0; 141.0 to before 153.0 Vulnerable ·Mozilla

Remediation

  • Fix · CNA Firefox (Mozilla) Fixed in 140.13, 153
  • Fix · CNA Thunderbird (Mozilla) Fixed in 140.13, 153

Red Hat 21 advisories

  • RHSA-2026:54339 Released 2026-08-12 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v.8.8) firefox-140.13.0-1.el8_8
    • Red Hat Enterprise Linux AppStream TUS (v.8.8) firefox-140.13.0-1.el8_8
  • RHSA-2026:54248 Released 2026-08-12 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux Server (v. 7 ELS) firefox-140.13.0-1.el7_9
  • RHSA-2026:54249 Released 2026-08-12 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) firefox-140.13.0-1.el9_6, firefox-x11-140.13.0-1.el9_6
Show 18 more Red Hat advisories
  • RHSA-2026:54259 Released 2026-08-12 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.6) firefox-140.13.0-1.el8_6
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) firefox-140.13.0-1.el8_6
  • RHSA-2026:54182 Released 2026-08-12 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.4) firefox-140.13.0-1.el9_4, firefox-x11-140.13.0-1.el9_4
  • RHSA-2026:54181 Released 2026-08-12 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) firefox-140.13.0-1.el10_0
  • RHSA-2026:54185 Released 2026-08-12 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) firefox-140.13.0-1.el9_2, firefox-x11-140.13.0-1.el9_2
  • RHSA-2026:54180 Released 2026-08-12 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) firefox-140.13.0-1.el8_4
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) firefox-140.13.0-1.el8_4
  • RHSA-2026:53475 Released 2026-08-11 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) thunderbird-140.13.0-1.el9_2
  • RHSA-2026:53454 Released 2026-08-11 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v.8.8) thunderbird-140.13.0-1.el8_8
    • Red Hat Enterprise Linux AppStream TUS (v.8.8) thunderbird-140.13.0-1.el8_8
  • RHSA-2026:53453 Released 2026-08-11 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.6) thunderbird-140.13.0-1.el8_6
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) thunderbird-140.13.0-1.el8_6
  • RHSA-2026:53455 Released 2026-08-11 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) thunderbird-140.13.0-1.el8_4
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) thunderbird-140.13.0-1.el8_4
  • RHSA-2026:53446 Released 2026-08-11 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) thunderbird-140.13.0-1.el9_6
  • RHSA-2026:53444 Released 2026-08-11 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.4) thunderbird-140.13.0-1.el9_4
  • RHSA-2026:53445 Released 2026-08-11 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) thunderbird-140.13.0-1.el10_0
  • RHSA-2026:49921 Released 2026-08-04 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 9) thunderbird-140.13.0-1.el9_8
  • RHSA-2026:49922 Released 2026-08-04 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 8) thunderbird-140.13.0-1.el8_10
  • RHSA-2026:49621 Released 2026-08-03 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 10) thunderbird-140.13.0-1.el10_2
  • RHSA-2026:47104 Released 2026-08-03 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 9) firefox-140.13.0-1.el9_8, firefox-x11-140.13.0-1.el9_8
  • RHSA-2026:47105 Released 2026-07-28 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 8) firefox-140.13.0-1.el8_10
  • RHSA-2026:47101 Released 2026-07-28 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 10) firefox-140.13.0-1.el10_2

Vendor assessments

Red Hat

Red Hat rating: Moderate. 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-2026:47101, RHSA-2026:49621
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2026:47105, RHSA-2026:49922
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:47104, RHSA-2026:49921
Red Hat Enterprise Linux AppStream AUS (v.8.4)Fixed RHSA-2026:53455, RHSA-2026:54180
Red Hat Enterprise Linux AppStream AUS (v.8.6)Fixed RHSA-2026:53453, RHSA-2026:54259
Red Hat Enterprise Linux AppStream E4S (v.8.8)Fixed RHSA-2026:53454, RHSA-2026:54339
Red Hat Enterprise Linux AppStream E4S (v.9.2)Fixed RHSA-2026:53475, RHSA-2026:54185
Red Hat Enterprise Linux AppStream E4S (v.9.4)Fixed RHSA-2026:53444, RHSA-2026:54182
Red Hat Enterprise Linux AppStream EUS (v. 10.0)Fixed RHSA-2026:53445, RHSA-2026:54181
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:53446, RHSA-2026:54249
Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)Fixed RHSA-2026:53455, RHSA-2026:54180
Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)Fixed RHSA-2026:53453, RHSA-2026:54259
Red Hat Enterprise Linux AppStream TUS (v.8.8)Fixed RHSA-2026:53454, RHSA-2026:54339
Red Hat Enterprise Linux Server (v. 7 ELS)Fixed RHSA-2026:54248

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-16379
  2. 2026-10-03 Alias added: GHSA-wh9f-q55j-mp9r

References

Advisory 4

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