CVE WatchSep 30, 2026

CVE-2025-4918

An attacker was able to perform an out-of-bounds read or write on a JavaScript `Promise` object. This vulnerability was fixed in Firefox 138

CVSS

9.8

Critical

EPSS

9.5%

p95

KEV

—

Exploit Today

0-100

Published: May 17, 2025 · Last modified: Sep 30, 2026 · CWE-125 · CWE-787

EPSS · 30d

9.4%EPSS · 30 days9.5%

2026-09-302026-10-28

Technical description

An attacker was able to perform an out-of-bounds read or write on a JavaScript `Promise` object. This vulnerability was fixed in Firefox 138.0.4, Firefox ESR 128.10.1, Firefox ESR 115.23.1, Thunderbird 128.10.2, and Thunderbird 138.0.2.

Official references

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