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TI-2026-07863 Aliases CVE-2026-8946GHSA-q9p7-4943-m5gr

Memory corruption in Mozilla Firefox

Priority MEDIUM 40CWE-119Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · None · None
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.

Summary

Incorrect boundary conditions in the Audio/Video: Web Codecs 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 0.0056 46th 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
Yes
Technical impact
Partial

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: 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-2026:21380, 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-2026-8946
  2. 2026-10-03 Alias added: GHSA-q9p7-4943-m5gr

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