TI-2026-81341 Aliases CVE-2026-118016 GHSA-65pv-f352-4j39

Use-after-free in Firefox and Thunderbird DOM component

MEDIUM 40CWE-416Published 2026-10-27 · Updated 2026-11-05

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: Fixed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-416 and the CVSS impact.

Summary

A use-after-free flaw in the DOM: Core & HTML component of Mozilla Firefox and Thunderbird allows memory corruption that can be triggered through user interaction. The weakness is classified as CWE-416 (Use After Free). The CVSS 3.1 base score is 8.8 (HIGH), and Red Hat rates it Important. Neither CISA nor the references list an exploit as known.

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

Description from the CNA

Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 159 and Thunderbird 159.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.0024 15th percentileScored 2026-11-07

Fix Fixed Firefox (Mozilla): 159Thunderbird (Mozilla): 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

Vendor	Product	Affected versions	Fixed in	Status	Source
Mozilla	Firefox	—	159	Patch available	CNA
Mozilla	Thunderbird	—	159	Patch available	CNA

Firefox VendorMozilla Affected — Fixed in 159 Patch available CNA
Thunderbird VendorMozilla Affected — Fixed in 159 Patch available CNA

CPE names Threatist (inferred) · 2

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

CPE	Versions	Role	Vendor
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

Update Firefox and Thunderbird to version 159 or later, which contains the fix.

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

Fix · CNA Firefox (Mozilla) Fixed in 159
Fix · CNA Thunderbird (Mozilla) Fixed in 159

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

Not affected: 5 products

Red Hat Enterprise Linux 10
Red Hat Enterprise Linux 6
Red Hat Enterprise Linux 7
Red Hat Enterprise Linux 8
Red Hat Enterprise Linux 9

Timeline

2026-10-27 Threatist record created from CVE-2026-118016
2026-10-27 Fix available: Mozilla/Thunderbird@159 · CNA
2026-10-27 1 new reference · CNA
2026-10-27 Alias added: GHSA-65pv-f352-4j39
2026-11-02 Affected versions changed · Red Hat
2026-11-02 CVSS score added · Red Hat
2026-11-05 CVSS score added · CISA ADP
2026-11-05 Weakness changed · CISA ADP
2026-11-05 CISA SSVC decision points changed
2026-11-07 Priority changed: LOW → MEDIUM

References

Other 3

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