CVE-2026-6758
published 2026-04-21CVE-2026-6758: Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.
PriorityP339high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.43%
34.8th percentile
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 150 | Firefox 150 |
| mozilla | firefox | < 150.0 | 150.0 |
| mozilla | thunderbird | < Thunderbird 150 | Thunderbird 150 |
| mozilla | thunderbird | < 150.0 | 150.0 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
vendor_redhat7.5HIGH
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Red Hat
firefox: Use-after-free in the JavaScript: WebAssembly component
vendor_redhat·2026-04-21·CVSS 7.5
CVE-2026-6758 [HIGH] CWE-825 firefox: Use-after-free in the JavaScript: WebAssembly component
firefox: Use-after-free in the JavaScript: WebAssembly component
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.
A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue:
Use-after-free in the JavaScript: WebAssembly component
Statement: Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Package: firefox (Red Hat Enterprise Linux 10) - Not affected
Package: firefox (Red Hat Enterprise Linux 7) - Not affected
Package: firefox (Red Hat Enterprise Linux 8) - Not affected
Package: firefox (Red Hat Enterprise Linux 9) - Not affected
Mozilla
Mozilla Foundation Security Advisory 2026-33: CVE-2026-6758
vendor_mozilla·CVSS 7.5
CVE-2026-6758 [HIGH] Mozilla Foundation Security Advisory 2026-33: CVE-2026-6758
Mozilla Foundation Security Advisory 2026-33
CVE: CVE-2026-6758
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 150
Mozilla
Mozilla Foundation Security Advisory 2026-30: CVE-2026-6758
vendor_mozilla·CVSS 7.5
CVE-2026-6758 [HIGH] Mozilla Foundation Security Advisory 2026-30: CVE-2026-6758
Mozilla Foundation Security Advisory 2026-30
CVE: CVE-2026-6758
Product: Firefox
Impact: high
Fixed in: Firefox 150
GHSA
GHSA-28xp-3gpw-3vvp: Use-after-free in the JavaScript: WebAssembly component
ghsa_unreviewed·2026-04-21
CVE-2026-6758 [HIGH] CWE-416 GHSA-28xp-3gpw-3vvp: Use-after-free in the JavaScript: WebAssembly component
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 150.
No detection rules found.
No public exploits indexed.
2026-04-21
Published