{"cve":"CVE-2023-35838","nvd":{"published":"2023-08-09T23:15:10.007","modified":"2026-06-17T06:05:18.313","status":"Modified","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","score":5.7},"cwes":["CWE-610"],"references":["https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2023-0015","https://tunnelcrack.mathyvanhoef.com/details.html","https://wireguard.com","https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2023-0015","https://tunnelcrack.mathyvanhoef.com/details.html"],"products":["wireguard:wireguard"],"source":"nvd","synced_at":"2026-10-19T21:39:14.809778102+00:00"},"epss":{"cve":"CVE-2023-35838","score":0.00689,"percentile":0.52781,"date":"2026-11-01"},"kev":null,"osv":[{"id":"PYSEC-2023-321","url":"https://osv.dev/vulnerability/PYSEC-2023-321","summary":"","modified":"2026-05-21T15:00:33.766466434Z","packages":[{"ecosystem":"PyPI","name":"wireguard","purl":"pkg:pypi/wireguard","ranges":["<=0.5.3"],"fixed":[]}]}],"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."]}