CVE-2026-4695
published 2026-03-24CVE-2026-4695: 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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VulDB
Mozilla Firefox up to 148 Web Codecs memory corruption (Nessus ID 303809 / WID-SEC-2026-0850)
vuldb·2026-04-16·CVSS 7.5
CVE-2026-4695 [HIGH] Mozilla Firefox up to 148 Web Codecs memory corruption (Nessus ID 303809 / WID-SEC-2026-0850)
A vulnerability marked as critical has been reported in Mozilla Firefox up to 148. This issue affects some unknown processing of the component Web Codecs. This manipulation causes memory corruption.
This vulnerability is handled as CVE-2026-4695. The attack can be initiated remotely. There is not any exploit available.
It is suggested to upgrade the affected component.
OSV
CVE-2026-4695: Incorrect boundary conditions in the Audio/Video: Web Codecs component
osv·2026-03-24·CVSS 7.5
CVE-2026-4695 [HIGH] CVE-2026-4695: 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.
GHSA
GHSA-vxpv-c2h6-hq9v: Incorrect boundary conditions in the Audio/Video: Web Codecs component
ghsa_unreviewed·2026-03-24
CVE-2026-4695 [HIGH] CWE-754 GHSA-vxpv-c2h6-hq9v: 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.
Red Hat
firefox: thunderbird: Incorrect boundary conditions in the Audio/Video: Web Codecs component
vendor_redhat·2026-03-24·CVSS 7.5
CVE-2026-4695 [HIGH] CWE-131 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-2026-4695: firefox - Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vul...
vendor_debian·2026·CVSS 7.5
CVE-2026-4695 [HIGH] CVE-2026-4695: 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 2026-24: CVE-2026-4695
vendor_mozilla·CVSS 7.5
CVE-2026-4695 [HIGH] Mozilla Foundation Security Advisory 2026-24: CVE-2026-4695
Mozilla Foundation Security Advisory 2026-24
CVE: CVE-2026-4695
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 140.9
Mozilla
Mozilla Foundation Security Advisory 2026-23: CVE-2026-4695
vendor_mozilla·CVSS 7.5
CVE-2026-4695 [HIGH] Mozilla Foundation Security Advisory 2026-23: CVE-2026-4695
Mozilla Foundation Security Advisory 2026-23
CVE: CVE-2026-4695
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 149
Mozilla
Mozilla Foundation Security Advisory 2026-22: CVE-2026-4695
vendor_mozilla·CVSS 7.5
CVE-2026-4695 [HIGH] Mozilla Foundation Security Advisory 2026-22: CVE-2026-4695
Mozilla Foundation Security Advisory 2026-22
CVE: CVE-2026-4695
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 140.9
Mozilla
Mozilla Foundation Security Advisory 2026-20: CVE-2026-4695
vendor_mozilla·CVSS 7.5
CVE-2026-4695 [HIGH] Mozilla Foundation Security Advisory 2026-20: CVE-2026-4695
Mozilla Foundation Security Advisory 2026-20
CVE: CVE-2026-4695
Product: Firefox
Impact: high
Fixed in: Firefox 149
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-4695 firefox: thunderbird: Incorrect boundary conditions in the Audio/Video: Web Codecs component
bugzilla·2026-03-24·CVSS 7.5
CVE-2026-4695 [HIGH] CVE-2026-4695 firefox: thunderbird: Incorrect boundary conditions in the Audio/Video: Web Codecs component
CVE-2026-4695 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-2026-4695 Impact, Exploitability, and Mitigation Steps | Wiz
blogs_wiz·CVSS 7.5
CVE-2026-4695 [HIGH] CVE-2026-4695 Impact, Exploitability, and Mitigation Steps | Wiz
## CVE-2026-4695 :
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
firefox-esr
firefox-x11
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 Added at: Mar 29, 2026
Debian 11,
https://bugzilla.mozilla.org/show_bug.cgi?id=2020030https://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-2026-4695https://bugzilla.redhat.com/show_bug.cgi?id=2450715https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4695.json
2026-03-24
Published