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 138.0.4, Firefox ESR 128.10.1, Firefox ESR 115.23.1, Thunderbird 128.10.2, and Thunderbird 138.0.2.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=1966612	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2025-36/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-37/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-38/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-40/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-41/	Vendor Advisory
https://lists.debian.org/debian-lts-announce/2025/05/msg00024.html
https://lists.debian.org/debian-lts-announce/2025/05/msg00046.html
https://www.vicarius.io/vsociety/posts/cve-2025-4918-detect-firefox-out-of-bounds-write	Exploit Third Party Advisory
https://www.vicarius.io/vsociety/posts/cve-2025-4918-mitigate-firefox-out-of-bounds-write	Exploit Third Party Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mozilla:firefox:::::esr:::*
	cpe:2.3:a:mozilla:firefox:::::-:::*
	cpe:2.3:a:mozilla:firefox:::::esr:::*
	cpe:2.3:a:mozilla:thunderbird::::::::
	cpe:2.3:a:mozilla:thunderbird:::::-:::*

History

No history.

Information

Published : 2025-05-17 22:15

Updated : 2026-06-17 09:34

NVD link : CVE-2025-4918

Mitre link : CVE-2025-4918

CVE.ORG link : CVE-2025-4918

JSON object : View

Products Affected

mozilla

thunderbird
firefox

CWE

CWE-125

Out-of-bounds Read

CWE-787

Out-of-bounds Write

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