Unauthenticated hostname restriction bypass via crafted request
Published Mar 10, 2026 · Updated Mar 10, 2026
Authentication bypass in Fortinet FortiWeb 7.0, 7.2, 7.4.0 through 7.4.8, and 7.6.0 through 7.6.3 lets remote attackers evade hostname restrictions. The protected-hostname feature accepts a specially crafted request that defeats matching against allowed HTTP Host values; Fortinet has not disclosed the exact parsing or normalization error. Exploitation requires a network-reachable policy using protected hostnames and permits traffic under a disallowed hostname, without reported data disclosure or service interruption.
Summary
What happened
Authentication bypass in Fortinet FortiWeb 7.0, 7.2, 7.4.0 through 7.4.8, and 7.6.0 through 7.6.3 lets remote attackers evade hostname restrictions. The protected-hostname feature accepts a specially crafted request that defeats matching against allowed HTTP Host values; Fortinet has not disclosed the exact parsing or normalization error. Exploitation requires a network-reachable policy using protected hostnames and permits traffic under a disallowed hostname, without reported data disclosure or service interruption.
The record
- CVE
- CVE-2025-48840
- Published
- Mar 10, 2026
- Updated
- Mar 10, 2026
- Vendor
- Fortinet
- Product
- FortiWeb
- Classifications
- CWE-290, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 10, 2026CVE publishedPublication date reported by the CVE source.
- Mar 10, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=7.0.0 <=7.0.12
- Affected versionversion=7.2.0 <=7.2.12
- Affected versionversion=7.4.0 <=7.4.8
- Affected versionversion=7.6.0 <=7.6.3
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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