Privilege Escalation Vulnerability in WebRender Component of Firefox
CVE-2026-100797

Currently unrated

Key Information:

Vendor: Mozilla
Status: Firefox
Vendor: CVE Published:; 29 September 2026

What is CVE-2026-100797?

This vulnerability arises from a use-after-free issue in the WebRender component of Firefox, allowing attackers to exploit the flaw to escalate privileges. This can lead to unauthorized access to system resources. Mozilla has addressed this issue in several versions, including Firefox ESR 153.4, 157, 115.42, and 140.17. Users are encouraged to update their browsers to mitigate the risk associated with this vulnerability.

Affected Version(s)

Firefox 115.42

Firefox 140.17

Firefox 153.4

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2050542

https://www.mozilla.org/security/advisories/mfsa2026-100/

https://www.mozilla.org/security/advisories/mfsa2026-97/

Download the Critical Vulnerability Management Cheat Sheet

Timeline

Vulnerability published
Sep 29, 2026
Vulnerability Reserved
Sep 26, 2026

Credit

Mozilla

CVE-2026-100797 Data

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