CVE-2024-3661

Public Exploit
DHCP routing options can manipulate interface-based VPN traffic

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.

Category

7.6
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.82% Top 30%
Vendor Advisory cisco.com Vendor Advisory fortinet.com Vendor Advisory f5.com Vendor Advisory paloaltonetworks.com Vendor Advisory citrix.com Vendor Advisory watchguard.com Vendor Advisory zscaler.com
Affected: IETF DHCP
Published at:
Updated at:

References

Link Tags
https://datatracker.ietf.org/doc/html/rfc2131#section-7 related
https://datatracker.ietf.org/doc/html/rfc3442#section-7 related
https://tunnelvisionbug.com/ third party advisory exploit
https://www.leviathansecurity.com/research/tunnelvision third party advisory
https://news.ycombinator.com/item?id=40279632 issue tracking
https://arstechnica.com/security/2024/05/novel-attack-against-virtually-all-vpn-apps-neuters-their-entire-purpose/ exploit press/media coverage
https://krebsonsecurity.com/2024/05/why-your-vpn-may-not-be-as-secure-as-it-claims/ exploit press/media coverage
https://issuetracker.google.com/issues/263721377 issue tracking
https://mullvad.net/en/blog/evaluating-the-impact-of-tunnelvision third party advisory
https://www.zscaler.com/blogs/security-research/cve-2024-3661-k-tunnelvision-exposes-vpn-bypass-vulnerability third party advisory vendor advisory exploit
https://lowendtalk.com/discussion/188857/a-rogue-dhcp-server-within-your-network-can-and-will-hijack-your-vpn-traffic issue tracking
https://news.ycombinator.com/item?id=40284111 issue tracking
https://www.agwa.name/blog/post/hardening_openvpn_for_def_con related
https://www.theregister.com/2024/05/07/vpn_tunnelvision_dhcp/ exploit press/media coverage
https://support.citrix.com/article/CTX677069/cloud-software-group-security-advisory-for-cve20243661 vendor advisory
https://www.watchguard.com/wgrd-psirt/advisory/wgsa-2024-00009 mitigation third party advisory vendor advisory
https://bst.cisco.com/quickview/bug/CSCwk05814 third party advisory vendor advisory
https://security.paloaltonetworks.com/CVE-2024-3661 vendor advisory
https://fortiguard.fortinet.com/psirt/FG-IR-24-170 vendor advisory
https://my.f5.com/manage/s/article/K000139553 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2024-3661?
CVE-2024-3661 has been scored as a high severity vulnerability.
How to fix CVE-2024-3661?
To fix CVE-2024-3661, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2024-3661 being actively exploited in the wild?
It is possible that CVE-2024-3661 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2024-3661?
CVE-2024-3661 affects IETF DHCP.
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