CVE-2024-3661
DHCP routing options can manipulate interface-based VPN traffic
Severity
High 7.6
CVSS 3.1
Exploited
Not listed
EPSS
0.041
89.7th percentile
Discovered by
Unknown
Published by the vendor
Published
May 6, 2024
Assigned by cisa-cg
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.
Weakness: CWE-306CWE-501
Affected products
| Vendor | Product | Category | Matched by |
|---|
No product mapping yet — this CVE is pending taxonomy review.
Vendor-reported affected versions (1)
- IETF · DHCP
References
- https://datatracker.ietf.org/doc/html/rfc2131#section-7
- https://datatracker.ietf.org/doc/html/rfc3442#section-7
- https://tunnelvisionbug.com/
- https://www.leviathansecurity.com/research/tunnelvision
- https://news.ycombinator.com/item?id=40279632
- https://arstechnica.com/security/2024/05/novel-attack-against-virtually-all-vpn-apps-neuters-their-entire-purpose/
- https://krebsonsecurity.com/2024/05/why-your-vpn-may-not-be-as-secure-as-it-claims/
- https://issuetracker.google.com/issues/263721377
- https://mullvad.net/en/blog/evaluating-the-impact-of-tunnelvision
- https://www.zscaler.com/blogs/security-research/cve-2024-3661-k-tunnelvision-exposes-vpn-bypass-vulnerability
- https://lowendtalk.com/discussion/188857/a-rogue-dhcp-server-within-your-network-can-and-will-hijack-your-vpn-traffic
- https://news.ycombinator.com/item?id=40284111
- https://www.agwa.name/blog/post/hardening_openvpn_for_def_con
- https://www.theregister.com/2024/05/07/vpn_tunnelvision_dhcp/
- https://support.citrix.com/article/CTX677069/cloud-software-group-security-advisory-for-cve20243661
- https://www.watchguard.com/wgrd-psirt/advisory/wgsa-2024-00009
- https://bst.cisco.com/quickview/bug/CSCwk05814
- https://security.paloaltonetworks.com/CVE-2024-3661
- https://fortiguard.fortinet.com/psirt/FG-IR-24-170
- https://my.f5.com/manage/s/article/K000139553