CVE-2026-4697
published 2026-03-24CVE-2026-4697: Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and…
PriorityP339high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.69%
48.6th percentile
Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.
Affected
10 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | firefox | < firefox 149.0-1 (sid) | firefox 149.0-1 (sid) |
| debian | firefox-esr | < firefox 149.0-1 (sid) | firefox 149.0-1 (sid) |
| debian | thunderbird | < firefox 149.0-1 (sid) | firefox 149.0-1 (sid) |
| mozilla | firefox | < 140.9.0 | 140.9.0 |
| mozilla | firefox | < 149.0 | 149.0 |
| mozilla | firefox | — | — |
| mozilla | thunderbird | >= 0 < 1:140.9.0esr-1~deb11u1 | 1:140.9.0esr-1~deb11u1 |
| mozilla | thunderbird | >= 0 < 1:140.9.0esr-1~deb12u1 | 1:140.9.0esr-1~deb12u1 |
| mozilla | thunderbird | >= 0 < 1:140.9.0esr-1~deb13u1 | 1:140.9.0esr-1~deb13u1 |
| mozilla | thunderbird | >= 0 < 1:140.9.0esr-1 | 1:140.9.0esr-1 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
osv7.5HIGH
vendor_debian7.5HIGH
vendor_redhat7.5HIGH
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Red Hat
firefox: thunderbird: Incorrect boundary conditions in the Audio/Video: Web Codecs component
vendor_redhat·2026-03-24·CVSS 7.5
CVE-2026-4697 [HIGH] CWE-787 firefox: thunderbird: Incorrect boundary conditions in the Audio/Video: Web Codecs component
firefox: thunderbird: Incorrect boundary conditions in the Audio/Video: Web Codecs component
Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability affects Firefox < 149, Firefox ESR < 140.9, Thunderbird < 149, and Thunderbird < 140.9.
A flaw was found in Firefox and Thunderbird. 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: rhel10/firefox-flatpak (Red Hat Enterprise Linux 10) - Affected
Package: rhel10/thunderbird-flatpak (Red Hat Enterprise Linux 10) - Affected
Package: firefox (Red Hat Enterprise Linux 6) - Out of
Debian
CVE-2026-4697: firefox - Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vul...
vendor_debian·2026·CVSS 7.5
CVE-2026-4697 [HIGH] CVE-2026-4697: firefox - Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vul...
Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability affects Firefox < 149, Firefox ESR < 140.9, Thunderbird < 149, and Thunderbird < 140.9.
Scope: local
sid: resolved (fixed in 149.0-1)
Mozilla
Mozilla Foundation Security Advisory 2026-23: CVE-2026-4697
vendor_mozilla·CVSS 7.5
CVE-2026-4697 [HIGH] Mozilla Foundation Security Advisory 2026-23: CVE-2026-4697
Mozilla Foundation Security Advisory 2026-23
CVE: CVE-2026-4697
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 149
Mozilla
Mozilla Foundation Security Advisory 2026-22: CVE-2026-4697
vendor_mozilla·CVSS 7.5
CVE-2026-4697 [HIGH] Mozilla Foundation Security Advisory 2026-22: CVE-2026-4697
Mozilla Foundation Security Advisory 2026-22
CVE: CVE-2026-4697
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 140.9
Mozilla
Mozilla Foundation Security Advisory 2026-24: CVE-2026-4697
vendor_mozilla·CVSS 7.5
CVE-2026-4697 [HIGH] Mozilla Foundation Security Advisory 2026-24: CVE-2026-4697
Mozilla Foundation Security Advisory 2026-24
CVE: CVE-2026-4697
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 140.9
Mozilla
Mozilla Foundation Security Advisory 2026-20: CVE-2026-4697
vendor_mozilla·CVSS 7.5
CVE-2026-4697 [HIGH] Mozilla Foundation Security Advisory 2026-20: CVE-2026-4697
Mozilla Foundation Security Advisory 2026-20
CVE: CVE-2026-4697
Product: Firefox
Impact: high
Fixed in: Firefox 149
VulDB
Mozilla Firefox up to 148 Web Codecs memory corruption (Nessus ID 303907 / WID-SEC-2026-0850)
vuldb·2026-04-16·CVSS 7.5
CVE-2026-4697 [HIGH] Mozilla Firefox up to 148 Web Codecs memory corruption (Nessus ID 303907 / WID-SEC-2026-0850)
A vulnerability, which was classified as critical, has been found in Mozilla Firefox up to 148. This affects an unknown function of the component Web Codecs. The manipulation leads to memory corruption.
This vulnerability is referenced as CVE-2026-4697. Remote exploitation of the attack is possible. No exploit is available.
It is advisable to upgrade the affected component.
GHSA
GHSA-8768-346v-cvr2: Incorrect boundary conditions in the Audio/Video: Web Codecs component
ghsa_unreviewed·2026-03-24
CVE-2026-4697 [HIGH] CWE-754 GHSA-8768-346v-cvr2: Incorrect boundary conditions in the Audio/Video: Web Codecs component
Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9.
OSV
CVE-2026-4697: Incorrect boundary conditions in the Audio/Video: Web Codecs component
osv·2026-03-24·CVSS 7.5
CVE-2026-4697 [HIGH] CVE-2026-4697: Incorrect boundary conditions in the Audio/Video: Web Codecs component
Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability affects Firefox < 149, Firefox ESR < 140.9, Thunderbird < 149, and Thunderbird < 140.9.
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-4697 firefox: thunderbird: Incorrect boundary conditions in the Audio/Video: Web Codecs component
bugzilla·2026-03-24·CVSS 7.5
CVE-2026-4697 [HIGH] CVE-2026-4697 firefox: thunderbird: Incorrect boundary conditions in the Audio/Video: Web Codecs component
CVE-2026-4697 firefox: thunderbird: Incorrect boundary conditions in the Audio/Video: Web Codecs component
Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9.
Discussion:
This issue has been addressed in the following products:
Red Hat Enterprise Linux 10
Via RHSA-2026:5931 https://access.redhat.com/errata/RHSA-2026:5931
---
This issue has been addressed in the following products:
Red Hat Enterprise Linux 9
Via RHSA-2026:5930 https://access.redhat.com/errata/RHSA-2026:5930
---
This issue has been addressed in the following products:
Red Hat Enterprise Linux 8
Via RHSA-2026:5932 https://access.redhat.com/errata/RHSA-2026:5932
---
This issue has been addressed in the following products:
Red
Wiz
CVE-2026-4697 Impact, Exploitability, and Mitigation Steps | Wiz
blogs_wiz·CVSS 7.5
CVE-2026-4697 [HIGH] CVE-2026-4697 Impact, Exploitability, and Mitigation Steps | Wiz
## CVE-2026-4697 :
NixOS vulnerability analysis and mitigation
Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability affects Firefox < 149, Firefox ESR < 140.9, Thunderbird < 149, and Thunderbird < 140.9.
Source : NVD
## 7.5
Score
Published March 24, 2026
Severity HIGH
CNA Score 7.5
Affected Technologies
NixOS
Mozilla Firefox
Has Public Exploit No
Has CISA KEV Exploit No
CISA KEV Release Date N/A
CISA KEV Due Date N/A
Exploitation Probability Percentile (EPSS) 5.2
Exploitation Probability (EPSS) N/A
Affected packages and libraries
MozillaThunderbird
MozillaThunderbird-translations-common
Sources
AlmaLinux 8 Severity HIGH Has Fix Added at: Mar 31, 2026
AlmaLinux 9 Severity HIGH Has Fix Added at: Mar 31, 2026
Chainguard Has Fix A
https://bugzilla.mozilla.org/show_bug.cgi?id=2020422https://www.mozilla.org/security/advisories/mfsa2026-20/https://www.mozilla.org/security/advisories/mfsa2026-22/https://www.mozilla.org/security/advisories/mfsa2026-23/https://www.mozilla.org/security/advisories/mfsa2026-24/https://access.redhat.com/errata/RHSA-2026:5930https://access.redhat.com/errata/RHSA-2026:5931https://access.redhat.com/errata/RHSA-2026:5932https://access.redhat.com/errata/RHSA-2026:6188https://access.redhat.com/errata/RHSA-2026:6342https://access.redhat.com/errata/RHSA-2026:6917https://access.redhat.com/errata/RHSA-2026:7837https://access.redhat.com/errata/RHSA-2026:7838https://access.redhat.com/errata/RHSA-2026:7839https://access.redhat.com/errata/RHSA-2026:7840https://access.redhat.com/errata/RHSA-2026:7841https://access.redhat.com/errata/RHSA-2026:7842https://access.redhat.com/errata/RHSA-2026:7843https://access.redhat.com/errata/RHSA-2026:7845https://access.redhat.com/errata/RHSA-2026:7858https://access.redhat.com/errata/RHSA-2026:8284https://access.redhat.com/errata/RHSA-2026:8285https://access.redhat.com/errata/RHSA-2026:8286https://access.redhat.com/errata/RHSA-2026:8287https://access.redhat.com/errata/RHSA-2026:8288https://access.redhat.com/errata/RHSA-2026:8289https://access.redhat.com/errata/RHSA-2026:8290https://access.redhat.com/errata/RHSA-2026:8315https://access.redhat.com/errata/RHSA-2026:8427https://access.redhat.com/errata/RHSA-2026:8850https://access.redhat.com/security/cve/CVE-2026-4697https://bugzilla.redhat.com/show_bug.cgi?id=2450729https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4697.json
2026-03-24
Published