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TI-2026-07870 Aliases CVE-2026-8953GHSA-c3qv-mh67-fpxw

Use after free in Mozilla Firefox

Priority MEDIUM 44CWE-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

Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00532 45th percentileScored 2026-11-07
Fix Partial Firefox (Mozilla): 115.36, 140.11, 151Thunderbird (Mozilla): 140.11, 151Red 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—115.36, 140.11, 151Patch availableCNA
MozillaThunderbird—140.11, 151Patch availableCNA
  • Firefox VendorMozilla Affected — Fixed in 115.36, 140.11, 151 Patch available CNA
  • Thunderbird VendorMozilla Affected — Fixed in 140.11, 151 Patch available CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*before 115.36.0VulnerableMozilla
cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*before 151.0.0VulnerableMozilla
cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*140.0 to before 140.11.0VulnerableMozilla
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*before 140.11VulnerableMozilla
  • cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:* Versions before 115.36.0 Vulnerable ·Mozilla
  • cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:* Versions before 151.0.0 Vulnerable ·Mozilla
  • cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:* Versions 140.0 to before 140.11.0 Vulnerable ·Mozilla
  • cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* Versions before 140.11 Vulnerable ·Mozilla

Remediation

  • Fix · CNA Firefox (Mozilla) Fixed in 115.36, 140.11, 151
  • Fix · CNA Thunderbird (Mozilla) Fixed in 140.11, 151

Red Hat 21 advisories

  • RHSA-2026:27715 Released 2026-06-22 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) firefox-140.11.0-1.el10_0
  • RHSA-2026:26630 Released 2026-06-17 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v.8.8) firefox-140.11.0-1.el8_8
    • Red Hat Enterprise Linux AppStream TUS (v.8.8) firefox-140.11.0-1.el8_8
  • RHSA-2026:26629 Released 2026-06-17 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) firefox-140.11.0-1.el8_4
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) firefox-140.11.0-1.el8_4
Show 18 more Red Hat advisories
  • RHSA-2026:26606 Released 2026-06-17 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.6) firefox-140.11.0-1.el8_6
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) firefox-140.11.0-1.el8_6
  • RHSA-2026:26551 Released 2026-06-17 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux Server (v. 7 ELS) firefox-140.11.0-1.el7_9
  • RHSA-2026:26539 Released 2026-06-17 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) thunderbird-140.11.0-1.el10_0
  • RHSA-2026:26536 Released 2026-06-17 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.6) thunderbird-140.11.0-1.el8_6
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) thunderbird-140.11.0-1.el8_6
  • RHSA-2026:26521 Released 2026-06-17 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) thunderbird-140.11.0-1.el9_6
  • RHSA-2026:26492 Released 2026-06-17 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) firefox-140.11.0-1.el9_6, firefox-x11-140.11.0-1.el9_6
  • RHSA-2026:26493 Released 2026-06-17 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.4) firefox-140.11.0-1.el9_4, firefox-x11-140.11.0-1.el9_4
  • RHSA-2026:26491 Released 2026-06-17 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) firefox-140.11.0-1.el9_2, firefox-x11-140.11.0-1.el9_2
  • RHSA-2026:26268 Released 2026-06-16 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v.8.8) thunderbird-140.11.0-1.el8_8
    • Red Hat Enterprise Linux AppStream TUS (v.8.8) thunderbird-140.11.0-1.el8_8
  • RHSA-2026:26269 Released 2026-06-16 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) thunderbird-140.11.0-1.el9_2
  • RHSA-2026:26270 Released 2026-06-16 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) thunderbird-140.11.0-1.el8_4
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) thunderbird-140.11.0-1.el8_4
  • RHSA-2026:26174 Released 2026-06-16 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.4) thunderbird-140.11.0-1.el9_4
  • RHSA-2026:22643 Released 2026-06-03 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 8) thunderbird-140.11.0-1.el8_10
  • RHSA-2026:22325 Released 2026-06-01 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 10) thunderbird-140.11.0-1.el10_2
  • RHSA-2026:21378 Released 2026-05-27 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 9) firefox-140.11.0-1.el9_8, firefox-x11-140.11.0-1.el9_8
  • RHSA-2026:21381 Released 2026-05-27 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 9) thunderbird-140.11.0-1.el9_8
  • RHSA-2026:21380 Released 2026-05-27 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 10) firefox-140.11.0-1.el10_2
  • RHSA-2026:21382 Released 2026-05-27 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 8) firefox-140.11.0-1.el8_10

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-2026:21380, RHSA-2026:22325
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2026:21382, RHSA-2026:22643
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:21378, RHSA-2026:21381
Red Hat Enterprise Linux AppStream AUS (v.8.4)Fixed RHSA-2026:26270, RHSA-2026:26629
Red Hat Enterprise Linux AppStream AUS (v.8.6)Fixed RHSA-2026:26536, RHSA-2026:26606
Red Hat Enterprise Linux AppStream E4S (v.8.8)Fixed RHSA-2026:26268, RHSA-2026:26630
Red Hat Enterprise Linux AppStream E4S (v.9.2)Fixed RHSA-2026:26269, RHSA-2026:26491
Red Hat Enterprise Linux AppStream E4S (v.9.4)Fixed RHSA-2026:26174, RHSA-2026:26493
Red Hat Enterprise Linux AppStream EUS (v. 10.0)Fixed RHSA-2026:26539, RHSA-2026:27715
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:26492, RHSA-2026:26521
Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)Fixed RHSA-2026:26270, RHSA-2026:26629
Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)Fixed RHSA-2026:26536, RHSA-2026:26606
Red Hat Enterprise Linux AppStream TUS (v.8.8)Fixed RHSA-2026:26268, RHSA-2026:26630
Red Hat Enterprise Linux Server (v. 7 ELS)Fixed RHSA-2026:26551

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-8953
  2. 2026-10-03 Alias added: GHSA-c3qv-mh67-fpxw

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