Boundary condition flaw in Mozilla Firefox and Thunderbird playback
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-119 and the CVSS impact.
Summary
Mozilla Firefox and Thunderbird contain a flaw in the Audio/Video: Playback component caused by incorrect boundary conditions (CWE-119). A remote attacker without privileges can trigger it, but it requires user interaction. A successful attack can impact confidentiality and integrity, with no availability impact.
Written with Claude Haiku 5.5 from the sources below · 2026-11-04
Description from the CNA
Incorrect boundary conditions in the Audio/Video: Playback component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
Why it matters now
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 | — | 115.44, 153.6, 159 | Patch available | CNA |
| Mozilla | Thunderbird | — | 153.6, 159 | Patch available | CNA |
Remediation
Mozilla fixes this in Firefox 159, Firefox ESR 115.44 and Firefox ESR 153.6, and in Thunderbird 153.6 and Thunderbird 159. Update to one of these fixed versions or later.
Written with Claude Haiku 5.5 from the sources below · 2026-11-04
- Fix · CNA Firefox (Mozilla) Fixed in 115.44, 153.6, 159
- Fix · CNA Thunderbird (Mozilla) Fixed in 153.6, 159
Timeline
- 2026-10-27 Threatist record created from CVE-2026-117873
- 2026-10-27 Fix available: Mozilla/Thunderbird@159 · CNA
- 2026-10-27 1 new reference · CNA
- 2026-10-27 Fix available: Mozilla/[email protected] · CNA
- 2026-10-27 1 new reference · CNA
- 2026-10-27 Alias added: GHSA-hqh7-xf43-qv67
- 2026-11-04 CVSS score added · CISA ADP
- 2026-11-04 Weakness changed · CISA ADP
- 2026-11-04 CISA SSVC decision points changed
References
Other 6
- https://bugzilla.mozilla.org/show_bug.cgi?id=2071733
- https://www.mozilla.org/security/advisories/mfsa2026-118/
- https://www.mozilla.org/security/advisories/mfsa2026-119/
- https://www.mozilla.org/security/advisories/mfsa2026-120/
- https://www.mozilla.org/security/advisories/mfsa2026-121/
- https://www.mozilla.org/security/advisories/mfsa2026-122/
More Mozilla vulnerabilities
- 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
Sources
- CVE-2026-117873 · CVE Program
- CVE-2026-117873 · NVD
- FIRST EPSS
- GHSA-hqh7-xf43-qv67 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences