CVE-2026-74953

HighCVSS 8.8/10Last modified Aug 21, 2026

Description

Privilege escalation in the Networking: Cookies component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

Metrics

CVSS 3.1 8.8/10CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Weakness enumeration

CWE-269

Affected software

No affected versions have been published.

Timeline

Published
Aug 18, 2026
Last modified
Aug 21, 2026
NVD status
Analyzed

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CVE-2026-74953: High severity, CVSS 8.8 | Vulnix