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VULNERABILITIES

CVE-2026-100803 Details

Description

Same-origin policy bypass in the WebExtensions component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.

Metrics

CVSS 3.x Severity and Vector Strings:

No CVSS 3.x data is available for this CVE.

References to Advisories, Solutions, and Tools

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URLSource(s)Tag(s)
https://bugzilla.mozilla.org/show_bug.cgi?id=2057988 [email protected]
https://www.mozilla.org/security/advisories/mfsa2026-100/ [email protected]
https://www.mozilla.org/security/advisories/mfsa2026-101/ [email protected]
https://www.mozilla.org/security/advisories/mfsa2026-102/ [email protected]
https://www.mozilla.org/security/advisories/mfsa2026-103/ [email protected]

see all 8 references

Weakness Enumeration

No weakness enumeration is available for this CVE.

Affected Products

No affected product data is available for this CVE.

Change History

2 change records found show changes

QUICK INFO

CVE Dictionary Entry:
CVE-2026-100803
NVD Published Date:
Sep 29, 2026
NVD Last Modified:
Sep 30, 2026
Source:
[email protected]
CVE-2026-100803 Details - Not Deferred