CVE-2026-4699

Incorrect boundary conditions in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox 149, Firefox ESR 115.34, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.
References
Link Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2021863 Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-20/ Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-21/ Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-22/ Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-23/
https://www.mozilla.org/security/advisories/mfsa2026-24/
https://access.redhat.com/errata/RHSA-2026:5930
https://access.redhat.com/errata/RHSA-2026:5931
https://access.redhat.com/errata/RHSA-2026:5932
https://access.redhat.com/errata/RHSA-2026:6188
https://access.redhat.com/errata/RHSA-2026:6342
https://access.redhat.com/errata/RHSA-2026:6917
https://access.redhat.com/errata/RHSA-2026:7837
https://access.redhat.com/errata/RHSA-2026:7838
https://access.redhat.com/errata/RHSA-2026:7839
https://access.redhat.com/errata/RHSA-2026:7840
https://access.redhat.com/errata/RHSA-2026:7841
https://access.redhat.com/errata/RHSA-2026:7842
https://access.redhat.com/errata/RHSA-2026:7843
https://access.redhat.com/errata/RHSA-2026:7845
https://access.redhat.com/errata/RHSA-2026:7858
https://access.redhat.com/errata/RHSA-2026:8284
https://access.redhat.com/errata/RHSA-2026:8285
https://access.redhat.com/errata/RHSA-2026:8286
https://access.redhat.com/errata/RHSA-2026:8287
https://access.redhat.com/errata/RHSA-2026:8288
https://access.redhat.com/errata/RHSA-2026:8289
https://access.redhat.com/errata/RHSA-2026:8290
https://access.redhat.com/errata/RHSA-2026:8315
https://access.redhat.com/errata/RHSA-2026:8427
https://access.redhat.com/errata/RHSA-2026:8850
https://access.redhat.com/security/cve/CVE-2026-4699
https://bugzilla.redhat.com/show_bug.cgi?id=2450739
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4699.json
Configurations

Configuration 1 (hide)

OR cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*

History

30 Jun 2026, 03:20

Type Values Removed Values Added
References
  • () https://access.redhat.com/errata/RHSA-2026:5930 -
  • () https://access.redhat.com/errata/RHSA-2026:5931 -
  • () https://access.redhat.com/errata/RHSA-2026:5932 -
  • () https://access.redhat.com/errata/RHSA-2026:6188 -
  • () https://access.redhat.com/errata/RHSA-2026:6342 -
  • () https://access.redhat.com/errata/RHSA-2026:6917 -
  • () https://access.redhat.com/errata/RHSA-2026:7837 -
  • () https://access.redhat.com/errata/RHSA-2026:7838 -
  • () https://access.redhat.com/errata/RHSA-2026:7839 -
  • () https://access.redhat.com/errata/RHSA-2026:7840 -
  • () https://access.redhat.com/errata/RHSA-2026:7841 -
  • () https://access.redhat.com/errata/RHSA-2026:7842 -
  • () https://access.redhat.com/errata/RHSA-2026:7843 -
  • () https://access.redhat.com/errata/RHSA-2026:7845 -
  • () https://access.redhat.com/errata/RHSA-2026:7858 -
  • () https://access.redhat.com/errata/RHSA-2026:8284 -
  • () https://access.redhat.com/errata/RHSA-2026:8285 -
  • () https://access.redhat.com/errata/RHSA-2026:8286 -
  • () https://access.redhat.com/errata/RHSA-2026:8287 -
  • () https://access.redhat.com/errata/RHSA-2026:8288 -
  • () https://access.redhat.com/errata/RHSA-2026:8289 -
  • () https://access.redhat.com/errata/RHSA-2026:8290 -
  • () https://access.redhat.com/errata/RHSA-2026:8315 -
  • () https://access.redhat.com/errata/RHSA-2026:8427 -
  • () https://access.redhat.com/errata/RHSA-2026:8850 -
  • () https://access.redhat.com/security/cve/CVE-2026-4699 -
  • () https://bugzilla.redhat.com/show_bug.cgi?id=2450739 -
  • () https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4699.json -
CWE CWE-787

13 Apr 2026, 15:17

Type Values Removed Values Added
Summary (en) Incorrect boundary conditions in the Layout: Text and Fonts component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, Firefox ESR < 140.9, Thunderbird < 149, and Thunderbird < 140.9. (en) Incorrect boundary conditions in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox 149, Firefox ESR 115.34, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.

26 Mar 2026, 13:16

Type Values Removed Values Added
Summary
  • (es) Condiciones de contorno incorrectas en el componente Diseño: Texto y Fuentes. Esta vulnerabilidad afecta a Firefox &lt; 149, Firefox ESR &lt; 115.34, Firefox ESR &lt; 140.9, Thunderbird &lt; 149, y Thunderbird &lt; 140.9.

24 Mar 2026, 21:16

Type Values Removed Values Added
Summary (en) Incorrect boundary conditions in the Layout: Text and Fonts component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. (en) Incorrect boundary conditions in the Layout: Text and Fonts component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, Firefox ESR < 140.9, Thunderbird < 149, and Thunderbird < 140.9.
References
  • () https://www.mozilla.org/security/advisories/mfsa2026-23/ -
  • () https://www.mozilla.org/security/advisories/mfsa2026-24/ -

24 Mar 2026, 20:34

Type Values Removed Values Added
CWE CWE-754
References () https://bugzilla.mozilla.org/show_bug.cgi?id=2021863 - () https://bugzilla.mozilla.org/show_bug.cgi?id=2021863 - Permissions Required
References () https://www.mozilla.org/security/advisories/mfsa2026-20/ - () https://www.mozilla.org/security/advisories/mfsa2026-20/ - Vendor Advisory
References () https://www.mozilla.org/security/advisories/mfsa2026-21/ - () https://www.mozilla.org/security/advisories/mfsa2026-21/ - Vendor Advisory
References () https://www.mozilla.org/security/advisories/mfsa2026-22/ - () https://www.mozilla.org/security/advisories/mfsa2026-22/ - Vendor Advisory
CPE cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 7.5
First Time Mozilla
Mozilla firefox

24 Mar 2026, 13:16

Type Values Removed Values Added
New CVE

Information

Published : 2026-03-24 13:16

Updated : 2026-07-15 02:22


NVD link : CVE-2026-4699

Mitre link : CVE-2026-4699

CVE.ORG link : CVE-2026-4699


JSON object : View

Products Affected

mozilla

  • firefox
CWE
CWE-754

Improper Check for Unusual or Exceptional Conditions

CWE-787

Out-of-bounds Write