CVE-2026-100771: Vulnerability in Mozilla Firefox
Undefined behavior in the DOM: Streams component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
AI Analysis
Technical Summary
CVE-2026-100771 describes undefined behavior in the DOM: Streams component of Mozilla Firefox. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. The Mozilla advisory categorizes this issue as high impact and references Bug 2068336 for technical details. It is one of many vulnerabilities addressed in the September 2026 security update for Firefox ESR versions.
Potential Impact
The vulnerability has a high impact rating according to the Mozilla advisory. Undefined behavior in the DOM: Streams component could potentially lead to security issues such as sandbox escapes or memory corruption, but specific exploitation details are not provided. No known exploits in the wild have been reported at this time.
Mitigation Recommendations
The vulnerability has been fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. Users and administrators should update to these versions or later to mitigate this issue. No additional mitigation steps are indicated by the vendor advisory.
CVE-2026-100771: Vulnerability in Mozilla Firefox
Description
Undefined behavior in the DOM: Streams component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
Affected software
Mozilla
Firefox
pkg:github/mozilla/firefoxRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-100771 describes undefined behavior in the DOM: Streams component of Mozilla Firefox. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. The Mozilla advisory categorizes this issue as high impact and references Bug 2068336 for technical details. It is one of many vulnerabilities addressed in the September 2026 security update for Firefox ESR versions.
Potential Impact
The vulnerability has a high impact rating according to the Mozilla advisory. Undefined behavior in the DOM: Streams component could potentially lead to security issues such as sandbox escapes or memory corruption, but specific exploitation details are not provided. No known exploits in the wild have been reported at this time.
Mitigation Recommendations
The vulnerability has been fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. Users and administrators should update to these versions or later to mitigate this issue. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-26T19:15:27.479Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-100/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-97/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-98/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-99/","vendor":"Mozilla"}]
Threat ID: 6abbb3edf7a7c5410664096f
Added to database: 09/29/2026, 12:49:49 UTC
Last enriched: 09/29/2026, 13:33:18 UTC
Last updated: 09/29/2026, 18:20:13 UTC
Views: 3
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