CVE-2024-3661

CVE-2024-3661 is a high-severity vulnerability in Fortinet Forticlient with a CVSS 3.x base score of 7.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-306.

Key facts

Description

DHCP can add routes to a client’s routing table via the classless static route option (121). VPN-based security solutions that rely on routes to redirect traffic can be forced to leak traffic over the physical interface. An attacker on the same local network can read, disrupt, or possibly modify network traffic that was expected to be protected by the VPN.

Frequently asked questions

What is CVE-2024-3661?
DHCP can add routes to a client’s routing table via the classless static route option (121). VPN-based security solutions that rely on routes to redirect traffic can be forced to leak traffic over the physical interface. An attacker on the same local network can read, disrupt, or possibly modify network traffic that was expected to be protected by the VPN.
How severe is CVE-2024-3661?
CVE-2024-3661 has a CVSS 3.x base score of 7.6, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability low.
Is CVE-2024-3661 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-3661?
CVE-2024-3661 primarily affects Fortinet Forticlient. In total, 21 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2024-3661?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2024-3661 have an EU (EUVD) identifier?
Yes. CVE-2024-3661 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-32236.
When was CVE-2024-3661 published?
CVE-2024-3661 was published on 2024-05-06 and last updated on 2026-06-17.

References

Affected products (21)

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