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TI-2026-81186 Aliases CVE-2026-117860GHSA-wmwc-8q25-g888

Same-origin policy bypass in Mozilla Firefox and Thunderbird

Priority LOW 37CWE-346Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · None
Fix status
Partial Red Hat: 5 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-346.

Summary

Mozilla Firefox and Thunderbird contain a same-origin policy bypass in the DOM Navigation component, caused by an origin validation error (CWE-346). A remote unauthenticated attacker can bypass origin isolation if a user interacts with crafted content, with high impact to confidentiality and integrity.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

Description from the CNA

Same-origin policy bypass in the DOM: Navigation 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 0.00204 10th percentileScored 2026-11-07
Fix Partial Firefox (Mozilla): 153.6, 159Thunderbird (Mozilla): 153.6, 159Red Hat: 5 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—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

Update to Firefox 159, Firefox ESR 153.6, Thunderbird 159, or Thunderbird 153.6. Red Hat rates the issue Important and lists Red Hat Enterprise Linux 6 with no fix planned, and Red Hat Enterprise Linux 7, 8, 9, and 10 with no plan available.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

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

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 yet
Red Hat Enterprise Linux 8AffectedNo fix yet
Red Hat Enterprise Linux 9AffectedNo fix yet

Timeline

  1. 2026-10-27 Threatist record created from CVE-2026-117860
  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-wmwc-8q25-g888
  7. 2026-10-30 Affected versions changed · Red Hat
  8. 2026-10-30 CVSS score added · Red Hat
  9. 2026-11-04 CVSS score added · CISA ADP
  10. 2026-11-04 Weakness changed · CISA ADP
  11. 2026-11-04 CISA SSVC decision points changed

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