FortiProxy/OS Authenticated Proxy Bypass of Domain Fronting (7.0.1-7.6.3)
CVE-2025-25255 Published on October 14, 2025
An Improperly Implemented Security Check for Standard vulnerability [CWE-358] vulnerability in Fortinet FortiOS 7.6.0 through 7.6.3, FortiProxy 7.6.0 through 7.6.3, FortiProxy 7.4.0 through 7.4.11, FortiProxy 7.2 all versions, FortiProxy 7.0.1 through 7.0.22 may allow an unauthenticated proxy user to bypass the domain fronting protection feature via crafted HTTP requests.
Vulnerability Analysis
CVE-2025-25255 can be exploited with network access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality, with no impact on integrity, and no impact on availability.
Weakness Type
Improperly Implemented Security Check for Standard
The software does not implement or incorrectly implements one or more security-relevant checks as specified by the design of a standardized algorithm, protocol, or technique.
Products Associated with CVE-2025-25255
stack.watch emails you whenever new vulnerabilities are published in Fortinet FortiOS or Fortinet FortiProxy. Just hit a watch button to start following.
Affected Versions
Fortinet FortiOS:- Version 7.6.0, <= 7.6.3 is affected.
- Version 7.6.0, <= 7.6.3 is affected.
- Version 7.4.0, <= 7.4.11 is affected.
- Version 7.2.0, <= 7.2.15 is affected.
- Version 7.0.1, <= 7.0.22 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.