CVE-2023-42786 — A null pointer dereference in FortiOS versions 7

A null pointer dereference in FortiOS versions 7.4.0 through 7.4.1, 7.2.0 through 7.2.5, 7.0 all versions, 6.4 all versions , 6.2 all versions and 6.0 all versions allows attacker to trigger a denial of service via a crafted http request.

01What is this vulnerability?

A null pointer dereference in FortiOS versions 7.4.0 through 7.4.1, 7.2.0 through 7.2.5, 7.0 all versions, 6.4 all versions , 6.2 all versions and 6.0 all versions allows attacker to trigger a denial of service via a crafted http request.

02Affected products

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection in your stack of choice:

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07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2025-01-14T14:08:51.276Z
• Last modified: 2025-01-14T20:56:06.441Z

09References

• fortiguard.fortinet.com — https://fortiguard.fortinet.com/psirt/FG-IR-23-293