CVE-2026-8949 - Vulnerability Details - OpenCVE

Integer overflow in the Widget: Win32 component. This vulnerability was fixed in Firefox 151 and Firefox ESR 140.11.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable yes

Technical Impact partial

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Mozilla

Firefox

affected

Version	Status	Constraints
`140.11`	unaffected	≤ 140.*
`151`	unaffected	≤ *

No data.

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Project Subscriptions

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://bugzilla.mozilla.org/show_bug.cgi?id=1355639
https://www.mozilla.org/security/advisories/mfsa2026-46/
https://www.mozilla.org/security/advisories/mfsa2026-48/

History

Tue, 19 May 2026 14:15:00 +0000

Type	Values Removed	Values Added
Weaknesses		CWE-190
Metrics		cvssV3_1 `{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}` ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Tue, 19 May 2026 13:45:00 +0000

Type	Values Removed	Values Added
Description		Integer overflow in the Widget: Win32 component. This vulnerability was fixed in Firefox 151 and Firefox ESR 140.11.
Title		Integer overflow in the Widget: Win32 component
References		https://bugzilla.mozilla.org/show_bug.cgi?id=1355639 https://www.mozilla.org/security/advisories/mfsa2026-46/ https://www.mozilla.org/security/advisories/mfsa2026-48/

Projects

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MITRE

Status: PUBLISHED

Assigner: mozilla

Published: 2026-05-19T12:29:40.812Z

Updated: 2026-05-19T14:05:24.997Z

Reserved: 2026-05-19T12:29:40.080Z

Link: CVE-2026-8949

Vulnrichment

Updated: 2026-05-19T14:05:17.742Z

NVD

Status : Undergoing Analysis

Published: 2026-05-19T14:16:51.140

Modified: 2026-05-19T14:23:47.477

Link: CVE-2026-8949

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-190

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