Fortinet PSIRT AdvisoriesFG-IR-26-175

Improper limitation of a pathname to a restricted directory

CVSSv3 Score: 9.8 An Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') [CWE-22] and Improper Neutralization of NULL Byte or NULL Character [CWE-158] vulnerability may allow an unauthenticated attacker to write arbitrary files on the underlying system via crafted HTTP or HTTPS requests.This has been reported to be exploited in the wild, customers are urged to apply the workaround below. Revised on 2026-10-01 00:00:00

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9.8CVSS out of 10Critical severity

Scope

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Timeline

When this advisory changed

Oct 1, 2026 at 7:00 AM UTC
Published by Fortinet
The publication date reported by the vendor.
Oct 1, 2026 at 7:50 PM UTC
Added to SecurityAlert
We collected the advisory from the official source.
Oct 2, 2026 at 7:50 PM UTC
Confirmed at the source
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Vulnerabilities

CVEs named in this advisory

CVE-2026-104286View CVSS, KEV, EPSS, and threat context

Source

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Vendor: Fortinet
Advisory ID: FG-IR-26-175
Last source check: Oct 3, 2026 at 5:10 PM UTC

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What the vendor says is affected

When this advisory changed

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