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TI-2026-81325 Aliases CVE-2026-117999GHSA-5r42-vmxg-73hc

Race condition in Mozilla Firefox and Thunderbird IPC component

Priority MEDIUM 40CWE-362Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA.

Summary

Mozilla Firefox and Thunderbird contain a race condition in the IPC component. Improper synchronization of a shared resource (CWE-362) lets concurrent operations interfere with each other. A remote attacker without privileges can exploit it if a user interacts with attacker-controlled content, with high impact to confidentiality, integrity and availability.

Written with Claude Haiku 5.5 from the sources below · 2026-11-05

Description from the CNA

Race condition in the IPC component. This vulnerability was fixed in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00302 23rd percentileScored 2026-11-07
Fix Fixed Firefox (Mozilla): 153.6, 159Thunderbird (Mozilla): 153.6, 159

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—153.6, 159Patch availableCNA
MozillaThunderbird—153.6, 159Patch availableCNA
  • Firefox VendorMozilla Affected — Fixed in 153.6, 159 Patch available CNA
  • Thunderbird VendorMozilla Affected — Fixed in 153.6, 159 Patch available CNA

CPE names Threatist (inferred) · 2

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*——Mozilla
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*——Mozilla
  • cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:* Versions — — ·Mozilla
  • cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* Versions — — ·Mozilla

Remediation

Firefox is fixed in versions 159 and ESR 153.6, and Thunderbird is fixed in versions 159 and 153.6. Update to these fixed versions.

Written with Claude Haiku 5.5 from the sources below · 2026-11-05

  • Fix · CNA Firefox (Mozilla) Fixed in 153.6, 159
  • Fix · CNA Thunderbird (Mozilla) Fixed in 153.6, 159

Timeline

  1. 2026-10-27 Threatist record created from CVE-2026-117999
  2. 2026-10-27 Fix available: Mozilla/Thunderbird@159 · CNA
  3. 2026-10-27 1 new reference · CNA
  4. 2026-10-27 Fix available: Mozilla/[email protected] · CNA
  5. 2026-10-27 1 new reference · CNA
  6. 2026-10-27 Alias added: GHSA-5r42-vmxg-73hc
  7. 2026-11-05 CVSS score added · CISA ADP
  8. 2026-11-05 Weakness changed · CISA ADP
  9. 2026-11-05 CISA SSVC decision points changed
  10. 2026-11-07 Priority changed: LOW → MEDIUM

References

Other 5

  • 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 4204 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences