{"id":"CVE-2023-35838","aliases":["EUVD-2023-39833","GHSA-q424-r5hc-33qq","PYSEC-2023-321","UBUNTU-CVE-2023-35838"],"status":"published","title":"The WireGuard client 0.5.3 on Windows insecurely configures the operating system and firewall...","description":"The WireGuard client 0.5.3 on Windows insecurely configures the operating system and firewall such that traffic to a local network that uses non-RFC1918 IP addresses is blocked. This allows an adversary to trick the victim into blocking IP traffic to selected IP addresses and services even while the VPN is enabled. NOTE: the tunnelcrack.mathyvanhoef.com website uses this CVE ID to refer more generally to \"LocalNet attack resulting in the blocking of traffic\" rather than to only WireGuard.","severity":{"version":"3.1","score":5.7,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-12","score":0.00689,"percentile":0.53261,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-610"],"published":"2023-08-09T00:00:00Z","modified":"2026-10-28T02:30:50Z","affected":[{"source":"osv","ecosystem":"PyPI","package":"wireguard","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"0.5.3"}]}],"versions":["0.1.0","0.1.1","0.1.2","0.1.3","0.1.4","0.1.5","0.1.6","0.2.0","0.2.1","0.2.2","0.2.3","0.2.4","0.2.5","0.3.0","0.4.0"]},{"source":"osv","ecosystem":"Ubuntu:16.04:LTS","package":"wireguard","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.0.20200513-1~16.04.1","1.0.20200513-1~16.04.2"]},{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"wireguard","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.0.20200513-1~18.04.1","1.0.20200513-1~18.04.2"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"wireguard","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.0.20190913-1ubuntu1","0.0.20191212-1ubuntu1","0.0.20191219-1ubuntu1","1.0.20200102-1ubuntu1","1.0.20200121-1ubuntu1","1.0.20200121-2ubuntu1","1.0.20200206-1ubuntu1","1.0.20200206-2ubuntu1","1.0.20200319-1ubuntu1","1.0.20200513-1~20.04.1","1.0.20200513-1~20.04.2"]},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"wireguard","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.0.20210424-1ubuntu1","1.0.20210914-1ubuntu1","1.0.20210914-1ubuntu2"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"wireguard","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.0.20210914-1ubuntu3","1.0.20210914-1ubuntu4"]}],"products":[{"vendor":"wireguard","product":"wireguard"}],"references":[{"url":"https://wireguard.com","tags":["x_transferred","Product","web"]},{"url":"https://tunnelcrack.mathyvanhoef.com/details.html","tags":["x_transferred","Exploit","Third Party Advisory","web","evidence","report"]},{"url":"https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2023-0015","tags":["x_transferred","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2023-35838","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-q424-r5hc-33qq"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/35xxx/CVE-2023-35838.json","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2023-35838","tags":["report"]},{"url":"https://papers.mathyvanhoef.com/usenix2023-tunnelcrack.pdf","tags":["report"]},{"url":"https://openvpn.net/security-advisory/statement-regarding-tunnelcrack-vulnerabilities/","tags":["report"]},{"url":"https://www.softether.org/9-about/News/905-TunnelCrack","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2023-35838","tags":["report"]},{"url":"https://security.paloaltonetworks.com/PAN-SA-2023-0004","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2023-35838","description":"The WireGuard client 0.5.3 on Windows insecurely configures the operating system and firewall such that traffic to a local network that uses non-RFC1918 IP addresses is blocked. This allows an adversary to trick the victim into blocking IP traffic to selected IP addresses and services even while the VPN is enabled. NOTE: the tunnelcrack.mathyvanhoef.com website uses this CVE ID to refer more generally to \"LocalNet attack resulting in the blocking of traffic\" rather than to only WireGuard.","status":"published","published":"2023-08-09T00:00:00Z","modified":"2024-10-18T19:02:08.462Z","updated_at":"2026-11-02T14:35:33.462059Z"}],"euvd":[{"id":"EUVD-2023-39833","description":"The WireGuard client 0.5.3 on Windows insecurely configures the operating system and firewall such that traffic to a local network that uses non-RFC1918 IP addresses is blocked. This allows an adversary to trick the victim into blocking IP traffic to selected IP addresses and services even while the VPN is enabled. NOTE: the tunnelcrack.mathyvanhoef.com website uses this CVE ID to refer more generally to \"LocalNet attack resulting in the blocking of traffic\" rather than to only WireGuard.","status":"published","published":"2023-08-09T00:00:00Z","modified":"2024-10-18T19:02:08Z","updated_at":"2026-11-03T00:27:32.691525Z"}],"ghsa":[{"id":"GHSA-q424-r5hc-33qq","title":"The WireGuard client 0.5.3 on Windows insecurely configures the operating system and firewall...","description":"The WireGuard client 0.5.3 on Windows insecurely configures the operating system and firewall such that traffic to a local network that uses non-RFC1918 IP addresses is blocked. This allows an adversary to trick the victim into blocking IP traffic to selected IP addresses and services even while the VPN is enabled. NOTE: the tunnelcrack.mathyvanhoef.com website uses this CVE ID to refer more generally to \"LocalNet attack resulting in the blocking of traffic\" rather than to only WireGuard.","status":"published","published":"2023-08-10T00:30:52Z","modified":"2024-04-04T06:45:59Z","cvss":[{"version":"3.1","score":5.7,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-610"],"updated_at":"2026-11-02T14:56:45.438001Z"}],"nvd":[{"id":"CVE-2023-35838","description":"The WireGuard client 0.5.3 on Windows insecurely configures the operating system and firewall such that traffic to a local network that uses non-RFC1918 IP addresses is blocked. This allows an adversary to trick the victim into blocking IP traffic to selected IP addresses and services even while the VPN is enabled. NOTE: the tunnelcrack.mathyvanhoef.com website uses this CVE ID to refer more generally to \"LocalNet attack resulting in the blocking of traffic\" rather than to only WireGuard.","status":"published","published":"2023-08-09T23:15:10.007Z","modified":"2026-06-17T06:05:18.313Z","cvss":[{"version":"3.1","score":5.7,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium","assessor":"primary"}],"cwes":["CWE-610"],"updated_at":"2026-11-02T14:08:22.812138Z"}],"osv":[{"id":"PYSEC-2023-321","description":"The WireGuard client 0.5.3 on Windows insecurely configures the operating system and firewall such that traffic to a local network that uses non-RFC1918 IP addresses is blocked. This allows an adversary to trick the victim into blocking IP traffic to selected IP addresses and services even while the VPN is enabled. NOTE: the tunnelcrack.mathyvanhoef.com website uses this CVE ID to refer more generally to \"LocalNet attack resulting in the blocking of traffic\" rather than to only WireGuard.","status":"published","published":"2023-08-09T23:15:10.007Z","modified":"2026-05-21T15:00:33.766466434Z","cvss":[{"version":"3.1","score":5.7,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T15:52:53.837392Z"},{"id":"UBUNTU-CVE-2023-35838","description":"The WireGuard client 0.5.3 on Windows insecurely configures the operating system and firewall such that traffic to a local network that uses non-RFC1918 IP addresses is blocked. This allows an adversary to trick the victim into blocking IP traffic to selected IP addresses and services even while the VPN is enabled. NOTE: the tunnelcrack.mathyvanhoef.com website uses this CVE ID to refer more generally to \"LocalNet attack resulting in the blocking of traffic\" rather than to only WireGuard.","status":"published","published":"2023-08-09T23:15:00Z","modified":"2026-01-20T17:36:51.506827Z","cvss":[{"version":"3.1","score":5.7,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T16:54:21.882004Z"},{"id":"CVE-2023-35838","description":"The WireGuard client 0.5.3 on Windows insecurely configures the operating system and firewall such that traffic to a local network that uses non-RFC1918 IP addresses is blocked. This allows an adversary to trick the victim into blocking IP traffic to selected IP addresses and services even while the VPN is enabled. NOTE: the tunnelcrack.mathyvanhoef.com website uses this CVE ID to refer more generally to \"LocalNet attack resulting in the blocking of traffic\" rather than to only WireGuard.","status":"published","published":"2023-08-09T00:00:00Z","modified":"2026-10-28T02:30:50.7053281Z","updated_at":"2026-11-02T15:44:32.510144Z"}]}}