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TI-2025-09642 Aliases CVE-2025-10537GHSA-579p-jcg6-h5r2

Memory safety bugs fixed in Firefox ESR 140.3, Thunderbird ESR 140.3, Firefox 143 and Thunderbird 143

Priority MEDIUM 40CWE-119Published · 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: 15 fixed, 3 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-119 and the CVSS impact.

Summary

Memory safety bugs present in Firefox ESR 140.2, Thunderbird ESR 140.2, Firefox 142 and Thunderbird 142. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 143, Firefox ESR 140.3, Thunderbird 143, and Thunderbird 140.3.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00339 27th percentileScored 2026-11-07
Fix Partial Firefox (Mozilla): 140.3, 143Thunderbird (Mozilla): 140.3, 143Red Hat: 21 advisoriesRed Hat: 15 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—140.3, 143Patch availableCNA
MozillaThunderbird—140.3, 143Patch availableCNA
  • Firefox VendorMozilla Affected — Fixed in 140.3, 143 Patch available CNA
  • Thunderbird VendorMozilla Affected — Fixed in 140.3, 143 Patch available CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*before 140.3.0VulnerableMozilla
cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*before 143.0VulnerableMozilla
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*before 140.3.0VulnerableMozilla
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*before 143.0VulnerableMozilla
  • cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:* Versions before 140.3.0 Vulnerable ·Mozilla
  • cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:* Versions before 143.0 Vulnerable ·Mozilla
  • cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:* Versions before 140.3.0 Vulnerable ·Mozilla
  • cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:* Versions before 143.0 Vulnerable ·Mozilla

Remediation

  • Fix · CNA Firefox (Mozilla) Fixed in 140.3, 143
  • Fix · CNA Thunderbird (Mozilla) Fixed in 140.3, 143

Red Hat 21 advisories

  • RHSA-2025:17453 Released 2025-10-07 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux Server (v. 7 ELS) firefox-140.3.0-1.el7_9
  • RHSA-2025:17378 Released 2025-10-06 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.4) firefox-140.3.0-1.el9_4, firefox-x11-140.3.0-1.el9_4
  • RHSA-2025:17374 Released 2025-10-06 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) firefox-140.3.0-1.el9_2, firefox-x11-140.3.0-1.el9_2
Show 18 more Red Hat advisories
  • RHSA-2025:17373 Released 2025-10-06 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.0) firefox-140.3.0-1.el9_0
  • RHSA-2025:17371 Released 2025-10-06 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) firefox-140.3.0-1.el8_4
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) firefox-140.3.0-1.el8_4
  • RHSA-2025:17372 Released 2025-10-06 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream AUS (v. 8.2) firefox-140.3.0-1.el8_2
  • RHSA-2025:17367 Released 2025-10-06 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.6) firefox-140.3.0-1.el8_6
    • Red Hat Enterprise Linux AppStream E4S (v.8.6) firefox-140.3.0-1.el8_6
    • Red Hat Enterprise Linux AppStream TUS (v.8.6) firefox-140.3.0-1.el8_6
  • RHSA-2025:17368 Released 2025-10-06 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v.8.8) firefox-140.3.0-1.el8_8
    • Red Hat Enterprise Linux AppStream TUS (v.8.8) firefox-140.3.0-1.el8_8
  • RHSA-2025:17346 Released 2025-10-06 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.4) thunderbird-140.3.0-1.el9_4
  • RHSA-2025:17345 Released 2025-10-06 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) thunderbird-140.3.0-1.el9_2
  • RHSA-2025:17343 Released 2025-10-06 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v.8.8) thunderbird-140.3.0-1.el8_8
    • Red Hat Enterprise Linux AppStream TUS (v.8.8) thunderbird-140.3.0-1.el8_8
  • RHSA-2025:17344 Released 2025-10-06 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.0) thunderbird-140.3.0-1.el9_0
  • RHSA-2025:17342 Released 2025-10-06 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.6) thunderbird-140.3.0-1.el8_6
    • Red Hat Enterprise Linux AppStream E4S (v.8.6) thunderbird-140.3.0-1.el8_6
    • Red Hat Enterprise Linux AppStream TUS (v.8.6) thunderbird-140.3.0-1.el8_6
  • RHSA-2025:17340 Released 2025-10-06 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream AUS (v. 8.2) thunderbird-140.3.0-1.el8_2
  • RHSA-2025:17341 Released 2025-10-06 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) thunderbird-140.3.0-1.el8_4
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) thunderbird-140.3.0-1.el8_4
  • RHSA-2025:16589 Released 2025-09-24 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 8) thunderbird-140.3.0-1.el8_10
  • RHSA-2025:16260 Released 2025-09-22 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 8) firefox-140.3.0-1.el8_10
  • RHSA-2025:16157 Released 2025-09-18 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 10) thunderbird-140.3.0-1.el10_0
  • RHSA-2025:16156 Released 2025-09-18 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 9) thunderbird-140.3.0-1.el9_6
  • RHSA-2025:16108 Released 2025-09-17 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 9) firefox-140.3.0-1.el9_6, firefox-x11-140.3.0-1.el9_6
  • RHSA-2025:16109 Released 2025-09-17 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 10) firefox-140.3.0-1.el10_0

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-2025:16109, RHSA-2025:16157
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2025:16260, RHSA-2025:16589
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2025:16108, RHSA-2025:16156
Red Hat Enterprise Linux AppStream AUS (v. 8.2)Fixed RHSA-2025:17340, RHSA-2025:17372
Red Hat Enterprise Linux AppStream AUS (v.8.4)Fixed RHSA-2025:17341, RHSA-2025:17371
Red Hat Enterprise Linux AppStream AUS (v.8.6)Fixed RHSA-2025:17342, RHSA-2025:17367
Red Hat Enterprise Linux AppStream E4S (v.8.6)Fixed RHSA-2025:17342, RHSA-2025:17367
Red Hat Enterprise Linux AppStream E4S (v.8.8)Fixed RHSA-2025:17343, RHSA-2025:17368
Red Hat Enterprise Linux AppStream E4S (v.9.0)Fixed RHSA-2025:17344, RHSA-2025:17373
Red Hat Enterprise Linux AppStream E4S (v.9.2)Fixed RHSA-2025:17345, RHSA-2025:17374
Red Hat Enterprise Linux AppStream EUS (v.9.4)Fixed RHSA-2025:17346, RHSA-2025:17378
Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)Fixed RHSA-2025:17341, RHSA-2025:17371
Red Hat Enterprise Linux AppStream TUS (v.8.6)Fixed RHSA-2025:17342, RHSA-2025:17367
Red Hat Enterprise Linux AppStream TUS (v.8.8)Fixed RHSA-2025:17343, RHSA-2025:17368
Red Hat Enterprise Linux Server (v. 7 ELS)Fixed RHSA-2025:17453

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-10537
  2. 2026-10-03 Alias added: GHSA-579p-jcg6-h5r2

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