VULNERABILITY INTELLIGENCE

CVE-2023-36673

CVSS score7.3 HIGH
EPSS probability0.53%
CISA KEVNot currently listed
Published2023-08-09
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N

Description

An issue was discovered in Avira Phantom VPN through 2.23.1 for macOS. The VPN client insecurely configures the operating system such that all IP traffic to the VPN server's IP address is sent in plaintext outside the VPN tunnel, even if this traffic is not generated by the VPN client, while simultaneously using plaintext DNS to look up the VPN server's IP address. This allows an adversary to trick the victim into sending traffic to arbitrary IP addresses in plaintext outside the VPN tunnel. NOTE: the tunnelcrack.mathyvanhoef.com website uses this CVE ID to refer more generally to "ServerIP attack, combined with DNS spoofing, that can leak traffic to an arbitrary IP address" rather than to only Avira Phantom VPN.

Weakness classification

  • nvd@nist.gov: CWE-319

Primary references