File-Filter Bypass in Explicit Web Proxy Policy

Summary

An Improper Neutralization of CRLF Sequences in HTTP Headers ('http response splitting') vulnerability [CWE-113] in FortiOS, FortiProxy and FortiSASE may allow a remote unauthenticated attacker to bypass the file filter via crafted HTTP header.

Version Affected Solution
FortiOS 7.6 7.6.0 Upgrade to 7.6.1 or above
FortiOS 7.4 7.4.0 through 7.4.4 Upgrade to 7.4.5 or above
FortiOS 7.2 7.2.0 through 7.2.8 Upgrade to 7.2.9 or above
FortiOS 7.0 Not affected Not Applicable
FortiOS 6.4 Not affected Not Applicable
FortiProxy 7.6 Not affected Not Applicable
FortiProxy 7.4 7.4.0 through 7.4.5 Upgrade to 7.4.6 or above
FortiProxy 7.2 7.2.0 through 7.2.11 Upgrade to 7.2.12 or above
FortiProxy 7.0 Not affected Not Applicable
FortiProxy 2.0 Not affected Not Applicable
Follow the recommended upgrade path using our tool at: https://docs.fortinet.com/upgrade-tool

Fortinet in Q3/24 has remediated this issue in FortiSASE version 24.3.56 and hence the customers does not need to perform any action.

Acknowledgement

Fortinet is pleased to thank Li Daobing from Fortinet Development team for discovering and reporting this vulnerability internally.

Timeline

2025-01-14: Initial publication