vulnerability
Ubuntu: (CVE-2023-36672): openconnect vulnerability
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 6 | (AV:A/AC:M/Au:N/C:C/I:N/A:N) | Aug 9, 2023 | Jun 26, 2025 | Mar 27, 2026 |
Severity
6
CVSS
(AV:A/AC:M/Au:N/C:C/I:N/A:N)
Published
Aug 9, 2023
Added
Jun 26, 2025
Modified
Mar 27, 2026
Description
An issue was discovered in the Clario VPN client through 5.9.1.1662 for macOS. The VPN client insecurely configures the operating system such that traffic to the local network is sent in plaintext outside the VPN tunnel even if the local network is using a non-RFC1918 IP subnet. This allows an adversary to trick the victim into sending arbitrary IP traffic in plaintext outside the VPN tunnel. NOTE: the tunnelcrack.mathyvanhoef.com website uses this CVE ID to refer more generally to "LocalNet attack resulting in leakage of traffic in plaintext" rather than to only Clario.
Solution
no-fix-ubuntu-package
References
- CVE-2023-36672
- https://attackerkb.com/topics/CVE-2023-36672
- CWE-319
- EUVD-EUVD-2023-40615
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2023-40615
- https://openvpn.net/security-advisory/statement-regarding-tunnelcrack-vulnerabilities/
- https://papers.mathyvanhoef.com/usenix2023-tunnelcrack.pdf
- https://tunnelcrack.mathyvanhoef.com/details.html
- https://www.cve.org/CVERecord?id=CVE-2023-36672
- https://www.softether.org/9-about/News/905-TunnelCrack
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