CVE-2025-55018

An inconsistent interpretation of http requests ('http request smuggling') vulnerability in Fortinet FortiOS 7.6.0, FortiOS 7.4.0 through 7.4.9, FortiOS 7.2 all versions, FortiOS 7.0 all versions, FortiOS 6.4.3 through 6.4.16 may allow an unauthenticated attacker to smuggle an unlogged http request through the firewall policies via a specially crafted header

Published: 2026-02-10 Last update: 2026-05-12 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2025-55018 is rated Low Risk (29/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.05%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-55018

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-02-24 0.03% 0.05% +0.02%
2 2026-02-11 0.03%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-55018

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.8 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 1.4 [email protected]

Weakness enumeration for CVE-2025-55018

GitHub Security Advisory for CVE-2025-55018

GHSA-7hxv-xg9w-4xg7 · Severity: medium — An inconsistent interpretation of http requests ('http request smuggling') vulnerability in...

Affected software / configurations for CVE-2025-55018

Vendor Product Version Raw CPE
fortinet fortios >= 6.4.3, <= 6.4.16 cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios >= 7.0.0, < 7.4.10 cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
fortinet fortios 7.6.0 cpe:2.3:o:fortinet:fortios:7.6.0:*:*:*:*:*:*:*

References for CVE-2025-55018

cvelogic Threat Intelligence