Buffer overflow in Mozilla products - CVE-2026-5734
Published: April 7, 2026
Vulnerability identifier: #VU125090
CSH Severity: High
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber
CVE-ID: CVE-2026-5734
CWE-ID: CWE-119
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Mozilla
Affected software:
Mozilla Firefox
Firefox ESR
Firefox for Android
Mozilla Firefox
Firefox ESR
Firefox for Android
Detailed vulnerability description
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a boundary error when processing HTML content. A remote attacker can trick the victim into visiting a specially crafted website, trigger memory corruption and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
How to mitigate CVE-2026-5734
Install updates from vendor's website.
Sources
- https://www.mozilla.org/en-US/security/advisories/mfsa2026-27/
- https://www.mozilla.org/en-US/security/advisories/mfsa2026-25/
- https://bugzilla.mozilla.org/buglist.cgi?bug_id=2022369
- https://bugzilla.mozilla.org/buglist.cgi?bug_id=2023026
- https://bugzilla.mozilla.org/buglist.cgi?bug_id=2023545
- https://bugzilla.mozilla.org/buglist.cgi?bug_id=2023555
- https://bugzilla.mozilla.org/buglist.cgi?bug_id=2023958
- https://bugzilla.mozilla.org/buglist.cgi?bug_id=2025422
- https://bugzilla.mozilla.org/buglist.cgi?bug_id=2025468
- https://bugzilla.mozilla.org/buglist.cgi?bug_id=2025492
- https://bugzilla.mozilla.org/buglist.cgi?bug_id=2025505