Cyber Resilience

CVE-2026-12293

CriticalUpdated

Published: 16 June 2026

Published
16 June 2026
Modified
30 June 2026
KEV Added
Patch
CVSS Score v3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0030 21.9th percentile
Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2026-12293 is a critical-severity Use After Free (CWE-416) vulnerability in Mozilla Firefox. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Drive-by Compromise (T1189); ranked at the 21.9th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

Use-after-free in the Graphics: WebGPU component. This vulnerability was fixed in Firefox 152 and Thunderbird 152.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1189 Drive-by Compromise Initial Access
Adversaries may gain access to a system through a user visiting a website over the normal course of browsing.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
Why these techniques?

Use-after-free in browser graphics component directly enables drive-by client exploitation via malicious web content leading to code execution.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

Affected Assets

mozilla
firefox
≤ 152.0.0
mozilla
thunderbird
≤ 152.0.0

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-416

Use-after-free exploits that achieve arbitrary code execution are blocked or significantly hardened by non-executable pages and ASLR.

References