Fortinet PSIRT AdvisoriesFG-IR-26-157

Content-Encoding WAF Evasion

CVSSv3 Score: 4.8 An incomplete list of disallowed inputs [CWE-184] in FortiWeb WAF may allow an unauthenticated attacker to bypass policies via specifically crafted requests. Revised on 2026-08-12 00:00:00

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4.8CVSS out of 10Medium severity

Scope

What the vendor says is affected

FortiWeb

Timeline

When this advisory changed

Aug 12, 2026 at 7:00 AM UTC
Published by Fortinet
The publication date reported by the vendor.
Aug 20, 2026 at 2:50 AM UTC
Added to SecurityAlert
We collected the advisory from the official source.
Sep 13, 2026 at 4:50 AM UTC
Confirmed at the source
Our collector saw this advisory during a later source check.

Source

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Vendor: Fortinet
Advisory ID: FG-IR-26-157
Last source check: Sep 13, 2026 at 4:50 AM UTC

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What the vendor says is affected

When this advisory changed

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