{"cve":"CVE-2023-36673","nvd":{"published":"2023-08-09T23:15:10.897","modified":"2026-06-17T06:06:48.537","status":"Modified","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N","score":7.3},"cwes":["CWE-319"],"references":["https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2023-0015","https://tunnelcrack.mathyvanhoef.com/details.html","https://www.avira.com/en/free-vpn","https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2023-0015","https://tunnelcrack.mathyvanhoef.com/details.html"],"products":["avira:phantom_vpn"],"source":"nvd","synced_at":"2026-10-19T21:39:14.809778102+00:00"},"epss":{"cve":"CVE-2023-36673","score":0.00531,"percentile":0.44895,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}