CVE-2026-8946
published 2026-05-19CVE-2026-8946: Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11…
PriorityP341high7.5CVSS 3.1
AVNACLPRNUINSUCHINAN
EPSS
0.56%
42.8th percentile
Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Affected
11 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 151 | Firefox 151 |
| mozilla | firefox | < 115.36.0 | 115.36.0 |
| mozilla | firefox | < 151.0.0 | 151.0.0 |
| mozilla | firefox | — | — |
| mozilla | firefox | >= 140.0 < 140.11.0 | 140.11.0 |
| mozilla | firefox_esr | < Firefox ESR 115.36 | Firefox ESR 115.36 |
| mozilla | firefox_esr | < Firefox ESR 140.11 | Firefox ESR 140.11 |
| mozilla | thunderbird | < Thunderbird 151 | Thunderbird 151 |
| mozilla | thunderbird | < Thunderbird 140.11 | Thunderbird 140.11 |
| mozilla | thunderbird | < 140.11 | 140.11 |
| rhel10 | firefox-flatpak | — | — |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
vendor_redhat7.5HIGH
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Red Hat
firefox: Incorrect boundary conditions in the Audio/Video: Web Codecs component
vendor_redhat·2026-05-19·CVSS 7.5
CVE-2026-8946 [HIGH] CWE-787 firefox: Incorrect boundary conditions in the Audio/Video: Web Codecs component
firefox: Incorrect boundary conditions in the Audio/Video: Web Codecs component
A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue:
Incorrect boundary conditions in the Audio/Video: Web Codecs 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) - Affected
Package: rhel10/firefox-flatpak (Red Hat Enterprise Linux 10) - Affected
Package: firefox (Red Hat Enterprise Linux 6) - Out of support scope
Package: firefox (Red Hat Enterprise Linux 7) - Affected
Package: firefox (Red Hat Enterprise Linux 8) - Affected
Package: firefox (Red Hat Enterprise Linux 9) - Affected
Mozilla
Mozilla Foundation Security Advisory 2026-47: CVE-2026-8946
vendor_mozilla·CVSS 7.5
CVE-2026-8946 [HIGH] Mozilla Foundation Security Advisory 2026-47: CVE-2026-8946
Mozilla Foundation Security Advisory 2026-47
CVE: CVE-2026-8946
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 115.36
Mozilla
Mozilla Foundation Security Advisory 2026-50: CVE-2026-8946
vendor_mozilla·CVSS 7.5
CVE-2026-8946 [HIGH] Mozilla Foundation Security Advisory 2026-50: CVE-2026-8946
Mozilla Foundation Security Advisory 2026-50
CVE: CVE-2026-8946
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 151
Mozilla
Mozilla Foundation Security Advisory 2026-46: CVE-2026-8946
vendor_mozilla·CVSS 7.5
CVE-2026-8946 [HIGH] Mozilla Foundation Security Advisory 2026-46: CVE-2026-8946
Mozilla Foundation Security Advisory 2026-46
CVE: CVE-2026-8946
Product: Firefox
Impact: high
Fixed in: Firefox 151
Mozilla
Mozilla Foundation Security Advisory 2026-48: CVE-2026-8946
vendor_mozilla·CVSS 7.5
CVE-2026-8946 [HIGH] Mozilla Foundation Security Advisory 2026-48: CVE-2026-8946
Mozilla Foundation Security Advisory 2026-48
CVE: CVE-2026-8946
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 140.11
Mozilla
Mozilla Foundation Security Advisory 2026-51: CVE-2026-8946
vendor_mozilla·CVSS 7.5
CVE-2026-8946 [HIGH] Mozilla Foundation Security Advisory 2026-51: CVE-2026-8946
Mozilla Foundation Security Advisory 2026-51
CVE: CVE-2026-8946
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 140.11
GHSA
GHSA-q9p7-4943-m5gr: Incorrect boundary conditions in the Audio/Video: Web Codecs component
ghsa_unreviewed·2026-05-19
CVE-2026-8946 [HIGH] CWE-119 GHSA-q9p7-4943-m5gr: Incorrect boundary conditions in the Audio/Video: Web Codecs component
Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, and Firefox ESR 140.11.
VulDB
Mozilla Firefox up to 150 Web Codecs memory corruption (EUVD-2026-30894)
vuldb·2026-05-19·CVSS 7.5
CVE-2026-8946 [HIGH] Mozilla Firefox up to 150 Web Codecs memory corruption (EUVD-2026-30894)
A vulnerability was found in Mozilla Firefox up to 150. It has been classified as critical. This affects an unknown part of the component Web Codecs. This manipulation causes memory corruption.
This vulnerability appears as CVE-2026-8946. The attack may be initiated remotely. There is no available exploit.
Upgrading the affected component is recommended.
No detection rules found.
No public exploits indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=2029070https://www.mozilla.org/security/advisories/mfsa2026-46/https://www.mozilla.org/security/advisories/mfsa2026-47/https://www.mozilla.org/security/advisories/mfsa2026-48/https://www.mozilla.org/security/advisories/mfsa2026-50/https://www.mozilla.org/security/advisories/mfsa2026-51/https://access.redhat.com/errata/RHSA-2026:21378https://access.redhat.com/errata/RHSA-2026:21380https://access.redhat.com/errata/RHSA-2026:21381https://access.redhat.com/errata/RHSA-2026:21382https://access.redhat.com/errata/RHSA-2026:22325https://access.redhat.com/errata/RHSA-2026:22643https://access.redhat.com/errata/RHSA-2026:26174https://access.redhat.com/errata/RHSA-2026:26268https://access.redhat.com/errata/RHSA-2026:26269https://access.redhat.com/errata/RHSA-2026:26270https://access.redhat.com/errata/RHSA-2026:26491https://access.redhat.com/errata/RHSA-2026:26492https://access.redhat.com/errata/RHSA-2026:26493https://access.redhat.com/errata/RHSA-2026:26521https://access.redhat.com/errata/RHSA-2026:26536https://access.redhat.com/errata/RHSA-2026:26539https://access.redhat.com/errata/RHSA-2026:26551https://access.redhat.com/errata/RHSA-2026:26606https://access.redhat.com/errata/RHSA-2026:26629https://access.redhat.com/errata/RHSA-2026:26630https://access.redhat.com/errata/RHSA-2026:27715https://access.redhat.com/security/cve/CVE-2026-8946https://bugzilla.redhat.com/show_bug.cgi?id=2479849https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-8946.json
2026-05-19
Published