CVE-2026-100788
published 2026-09-29CVE-2026-100788: Invalid pointer in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird…
PriorityP349critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.44%
36.9th percentile
Invalid pointer in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, and Firefox ESR 140.17.
Affected
10 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 157 | Firefox 157 |
| mozilla | firefox | — | — |
| mozilla | firefox_esr | < Firefox ESR 140.17 | Firefox ESR 140.17 |
| mozilla | firefox_esr | < Firefox ESR 153.4 | Firefox ESR 153.4 |
| mozilla | thunderbird | < Thunderbird 140.17 | Thunderbird 140.17 |
| mozilla | thunderbird | < Thunderbird 157 | Thunderbird 157 |
| mozilla | thunderbird | < Thunderbird 153.4 | Thunderbird 153.4 |
| mozilla | thunderbird | — | — |
| rhel10 | firefox-flatpak | — | — |
| rhel10 | thunderbird-flatpak | — | — |
CVSS provenance
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
vendor_redhat9.8CRITICAL
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Red Hat
firefox: thunderbird: Invalid pointer in the JavaScript: WebAssembly component
vendor_redhat·2026-09-29·CVSS 9.8
CVE-2026-100788 [CRITICAL] CWE-824 firefox: thunderbird: Invalid pointer in the JavaScript: WebAssembly component
firefox: thunderbird: Invalid pointer in the JavaScript: WebAssembly component
Invalid pointer in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, and Firefox ESR 140.17.
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
Invalid pointer in the JavaScript: WebAssembly component
Statement: Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Mitigation: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widesprea
Mozilla
Mozilla Foundation Security Advisory 2026-99: CVE-2026-100788
vendor_mozilla
CVE-2026-100788 Mozilla Foundation Security Advisory 2026-99: CVE-2026-100788
Mozilla Foundation Security Advisory 2026-99
CVE: CVE-2026-100788
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 140.17
Mozilla
Mozilla Foundation Security Advisory 2026-97: CVE-2026-100788
vendor_mozilla
CVE-2026-100788 Mozilla Foundation Security Advisory 2026-97: CVE-2026-100788
Mozilla Foundation Security Advisory 2026-97
CVE: CVE-2026-100788
Product: Firefox
Impact: low
Fixed in: Firefox 157
Mozilla
Mozilla Foundation Security Advisory 2026-102: CVE-2026-100788
vendor_mozilla
CVE-2026-100788 Mozilla Foundation Security Advisory 2026-102: CVE-2026-100788
Mozilla Foundation Security Advisory 2026-102
CVE: CVE-2026-100788
Product: Thunderbird
Impact: moderate
Fixed in: Thunderbird 140.17
Mozilla
Mozilla Foundation Security Advisory 2026-100: CVE-2026-100788
vendor_mozilla
CVE-2026-100788 Mozilla Foundation Security Advisory 2026-100: CVE-2026-100788
Mozilla Foundation Security Advisory 2026-100
CVE: CVE-2026-100788
Product: Firefox ESR
Impact: low
Fixed in: Firefox ESR 153.4
Mozilla
Mozilla Foundation Security Advisory 2026-101: CVE-2026-100788
vendor_mozilla
CVE-2026-100788 Mozilla Foundation Security Advisory 2026-101: CVE-2026-100788
Mozilla Foundation Security Advisory 2026-101
CVE: CVE-2026-100788
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 157
Mozilla
Mozilla Foundation Security Advisory 2026-103: CVE-2026-100788
vendor_mozilla
CVE-2026-100788 Mozilla Foundation Security Advisory 2026-103: CVE-2026-100788
Mozilla Foundation Security Advisory 2026-103
CVE: CVE-2026-100788
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 153.4
GHSA
Invalid pointer in the JavaScript: WebAssembly component.
ghsa_unreviewed·2026-09-29
CVE-2026-100788 Invalid pointer in the JavaScript: WebAssembly component.
Invalid pointer in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17.
No detection rules found.
No public exploits indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=2072413https://www.mozilla.org/security/advisories/mfsa2026-100/https://www.mozilla.org/security/advisories/mfsa2026-101/https://www.mozilla.org/security/advisories/mfsa2026-102/https://www.mozilla.org/security/advisories/mfsa2026-103/https://www.mozilla.org/security/advisories/mfsa2026-97/https://www.mozilla.org/security/advisories/mfsa2026-99/
2026-09-29
Published