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CVE-2026-6771

Status: AnalyzedCritical (9.8)—

Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

Vector CVSS de acceso remoto sin autenticación (AV:N/PR:N) y bypass de mitigación de seguridad en DOM sugieren explotación de vulnerabilidad web expuesta (T1190). El bypass permite ejecución de código y potencial acceso a credenciales/sesiones.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Privileged Account ManagementApplication Developer GuidanceActive Directory ConfigurationVulnerability ScanningUser TrainingUser Account Management

Affected technologies (2)

Mozilla — FirefoxMozilla — Thunderbird

CWEs

References

Raw JSON (NVD)

Show
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