CVE-2026-109772

criticalpriority · track · 0EPSS 0.002 · 8 %ileDEFR

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.18% (8th) EPSS

CVSS 9.1 · critical

Is it mine?

10 products

Who says so?

2 sources

cert_bund · certfr

EPSS · scored 2026-10-27

Same-origin policy bypass in the DevTools component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.

cvss

Technical severity, 0–10. One row per scoring source.

9.1

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–critical · 6.1–9.1

v3.19.1criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Nsecondaryexploitability 3.9 · impact 5.2

v3.18.3highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nsecondary · grimoire (LLM-derived)LLM-inferred

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: totalcoordinatorcisa_ssvcUS

The CWE weakness classes this flaw belongs to.

Products and version ranges known to be affected.

Vendor and ecosystem advisories describing this.

WID-SEC-W-2026-3942Mozilla Firefox und Thunderbrid: Mehrere SchwachstellenDeutsch2026-10-13csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Mozilla Firefox und Mozilla Thunderbrid ausnutzen, um seine Privilegien zu erhöhen, Sicherheitsmaßnahmen zu umgehen, Spoofing-Angriffe durchzuführen, Daten offenzulegen oder zu manipulieren, Denial-of-Service-Zustände zu verursachen oder andere, nicht näher spezifizierte Angriffe durchzuführen.
CERTFR-2026-AVI-1305Multiples vulnérabilités dans les produits MozillaFrançais2026-10-14vendor · certfrFR

Which sources assert this record, and when.

published 2026-10-13modified 2026-10-26

External citations — patches, advisories, analysis.

scry

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