CVE-2026-16398

Status: AnalyzedHigh (7.5)—

Site isolation issue in the Graphics component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Base score: 7.5

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.15%
Percentile among all scored CVEs: 4
Score date: 10/5/2026

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.

ExploitationT1190 Exploit Public-Facing Applicationinitial access85 %
Primary impactT1005 Data from Local Systemcollection80 %

Vulnerabilidad de aislamiento de sitio en red sin autenticación (AV:N, PR:N, UI:N); acceso remoto a datos confidenciales en aplicación web (C:H). CWE-200 y T1005 sustentan lectura de información sensible.

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

Vulnerability Scanning Privileged Account Management Network Segmentation Limit Access to Resource Over Network Filter Network Traffic Application Isolation and Sandboxing

Affected technologies (2)

Mozilla — Firefox Mozilla — Thunderbird

CWEs

CWE-200, CWE-346

References

Raw JSON (NVD)

Show

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