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TI-2026-81334 Aliases CVE-2026-118009GHSA-4crp-78g8-rgh8

Integer overflow and use-after-free in Firefox and Thunderbird Graphics: Text

Priority MEDIUM 40CWE-190Published · 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
Fixed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-190 and the CVSS impact.

Summary

The Graphics: Text component in Mozilla Firefox and Thunderbird contains an integer overflow (CWE-190) and a use-after-free. The CVSS 3.1 base score is 8.8 (HIGH), with vector CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H, so an attacker who gets a user to interact can affect confidentiality, integrity and availability. Red Hat rates it Important. CISA has not added it to KEV, and the references include no exploit link.

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

Description from the CNA

Integer overflow, use-after-free in the Graphics: Text 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 0.00301 22nd 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

VendorProductAffected versionsFixed inStatusSource
MozillaFirefox—159Patch availableCNA
MozillaThunderbird—159Patch availableCNA
  • 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.

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

Update Firefox and Thunderbird to version 159, which fixes the issue.

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

  1. 2026-10-27 Threatist record created from CVE-2026-118009
  2. 2026-10-27 Fix available: Mozilla/Thunderbird@159 · CNA
  3. 2026-10-27 1 new reference · CNA
  4. 2026-10-27 Alias added: GHSA-4crp-78g8-rgh8
  5. 2026-11-02 Affected versions changed · Red Hat
  6. 2026-11-02 CVSS score added · Red Hat
  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 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