Incorrect boundary conditions in the Graphics: WebGPU component. This vulnerability was fixed in Firefox 149.0.2 and Thunderbird 149.0.2.
Conclusion & alert: CVE-2026-5733 is rated Moderate Risk (42.2/100): CVSS High severity, with low exploitation likelihood (EPSS 0.28%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-15 | 0.04% | 0.28% | +0.24% |
| 2 | 2026-04-08 | — | 0.04% | — |
Full EPSS history (2 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 8.8 | 3.1 | HIGH |
|
2.8 | 5.9 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
| vendor | priority | summary | link |
|---|---|---|---|
alpine
|
— | CVE-2026-5733: 1 source package rows (firefox); 128 state rows across 2 repos (3.23-community, edge-community); fixed 0, open 128. | https://security.alpinelinux.org/vuln/CVE-2026-5733 |
debian
|
not yet assigned | CVE-2026-5733 not yet assigned priority: Debian including 1 source packages (firefox), 1 status rows across 1 suites (sid): resolved 1. | https://security-tracker.debian.org/tracker/CVE-2026-5733 |
redhat
|
high | — | https://access.redhat.com/security/cve/CVE-2026-5733 |
suse
|
high | — | https://www.suse.com/security/cve/CVE-2026-5733/ |
ubuntu
|
medium | CVE-2026-5733 medium priority: Ubuntu including 9 source packages (firefox, mozjs102, …), 49 status rows across 7 suites (bionic, focal, jammy, noble, questing, resolute, upstream): DNE 23, needs-triage 10, ignored 8, not-affected 7, needed 1. | https://ubuntu.com/security/CVE-2026-5733 |
| URL | Tags |
|---|---|
| https://bugzilla.mozilla.org/show_bug.cgi?id=2022554 | Issue Tracking Permissions Required |
| https://www.mozilla.org/security/advisories/mfsa2026-25/ | Vendor Advisory |
| https://www.mozilla.org/security/advisories/mfsa2026-28/ |