How severe is CVE-2026-74966?

CVE-2026-74966 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-74966 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-74966?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2026-74966 published?

CVE-2026-74966 was published on 2026-08-18 and last updated on 2026-08-20.

CVE-2026-74966

CVE-2026-74966 is a high-severity vulnerability with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-359.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 0% (20th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-359
Published: 2026-08-18
Last modified: 2026-08-20

Description

Information disclosure in the Form Autofill component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.

Frequently asked questions

What is CVE-2026-74966?: Information disclosure in the Form Autofill component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.
How severe is CVE-2026-74966?: CVE-2026-74966 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-74966 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-74966?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2026-74966 published?: CVE-2026-74966 was published on 2026-08-18 and last updated on 2026-08-20.

References

Other CWE-359 vulnerabilities

CVE-2022-0482 — Critical (CVSS 9.1): Exposure of Private Personal Information to an Unauthorized Actor in GitHub repository alextselegidis/easyappointments…
CVE-2022-2921 — High (CVSS 8.8): Exposure of Private Personal Information to an Unauthorized Actor in GitHub repository notrinos/notrinoserp prior to…
CVE-2025-53625 — High (CVSS 8.7): The DynamicPageList3 extension is a reporting tool for MediaWiki, listing category members and intersections with…
CVE-2025-13008 — High (CVSS 8.6): An information disclosure vulnerability in M-Files Server before versions 25.12.15491.7, 25.8 LTS SR3, 25.2 LTS SR3 and…
CVE-2023-36052 — High (CVSS 8.6): Azure CLI REST Command Information Disclosure Vulnerability
CVE-2024-26192 — High (CVSS 8.2): Microsoft Edge (Chromium-based) Information Disclosure Vulnerability

Browse all CWE-359 vulnerabilities →