vulnerability
Fortinet FortiOS: CVE-2023-42789: Out-of-bounds Write in captive portal
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 10 | (AV:N/AC:L/Au:N/C:C/I:C/A:C) | Mar 12, 2024 | Mar 18, 2024 | Jun 23, 2026 |
Severity
10
CVSS
(AV:N/AC:L/Au:N/C:C/I:C/A:C)
Published
Mar 12, 2024
Added
Mar 18, 2024
Modified
Jun 23, 2026
Description
An out-of-bounds write vulnerability [CWE-787] and a Stack-based Buffer Overflow [CWE-121] in FortiOS & FortiProxy captive portal may allow an inside attacker who has access to captive portal to execute arbitrary code or commands via specially crafted HTTP requests.Workaround:Set a non form-based authentication scheme:config authentication schemeedit schemeset method methodnextendWhere <method> can be any of those :ntlm NTLM authentication.basic Basic HTTP authentication.digest Digest HTTP authentication.negotiate Negotiate authentication.fsso Fortinet Single Sign-On (FSSO) authentication.rsso RADIUS Single Sign-On (RSSO) authentication.ssh-publickey Public key based SSH authentication.cert Client certificate authentication.saml SAML authenticationNone of the enabled authentication schemes should be form-based.Please note that only devices with captive portal enabled are affected.
Solution
fortios-upgrade-latest
Rapid7 Labs
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