A interpretation conflict in Fortinet IPS Engine versions 7.321, 7.166 and 6.158 allows attacker to evade IPS features via crafted TCP pack…

published 2023-10-10 3 y ago modified 2026-06-17 4 mo ago also EUVD-2023-45272

cvss: 7.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 45%
public exploits: 0; none known

A interpretation conflict in Fortinet IPS Engine versions 7.321, 7.166 and 6.158 allows attacker to evade IPS features via crafted TCP packets.

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

cisa ICSA-24-074-11 updated 2026-01-14 cvss 7.5

Siemens RUGGEDCOM APE1808 with Fortigate NGFW Devices

Siemens RUGGEDCOM APE1808
affected: fixed in V7.4.1

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 2 y ago (2024-09-18)

Exploit prediction

0.53% chance of exploitation in the next 30 days, higher than 45% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	6.7	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N/E:F/RL:O/RC:R
CNA	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Affected products

Fortinet IPS Engine
fortinet fortios_ips_engine

Classification

Weakness

CWE-436 Interpretation Conflict

Technology feeds

Fortinet rss critical rss

References

fortiguard.com /psirt/FG-IR-23-090
vendor-advisory

Sources

CVE List CVE-2023-40718
NVD CVE-2023-40718

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary