A weak authentication in Fortinet FortiOS versions 7.4.0 through 7.4.4, 7.2.0 through 7.2.8, 7.0.0 through 7.0.15, 6.4.0 through 6.4.15, FortiProxy versions 7.4.0 through 7.4.4, 7.2.0 through 7.2.10, 7.0.0 through 7.0.17, 2.0.0 through 2.0.14, FortiManager versions 7.6.0 through 7.6.1, 7.4.1 through 7.4.3, FortiManager Cloud versions 7.4.1 through 7.4.3, FortiAnalyzer Cloud versions 7.4.1 through 7.4.3 allows attacker to execute unauthorized code or commands via a brute-force attack.
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 methodnextend
Where <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 authentication
None of the enabled authentication schemes should be form-based.
Please note that only devices with captive portal enabled are affected.
A out-of-bounds write vulnerability [CWE-787] in FortiOS and FortiProxy may allow a remote unauthenticated attacker to execute arbitrary code or command via specially crafted HTTP requests.
Workaround : disable SSL VPN (disable webmode is NOT a valid workaround)
Note: This is potentially being exploited in the wild.
An authentication bypass by assumed-immutable data vulnerability [CWE-302] in the FortiOS SSH login component 7.2.0, 7.0.0 through 7.0.7, 6.4.0 through 6.4.9, 6.2 all versions, 6.0 all versions and FortiProxy SSH login component 7.0.0 through 7.0.5, 2.0.0 through 2.0.10, 1.2.0 all versions may allow a remote and unauthenticated attacker to login into the device via sending specially crafted Access-Challenge response from the Radius server.