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CVE-2023-35838

Status: ModifiedMedium (5.7)—

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

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (1)

CWEs

References

Raw JSON (NVD)

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  "id": "CVE-2023-35838",
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          "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H",
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  "published": "2023-08-09T23:15:10.007",
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  "lastModified": "2026-06-17T06:05:18.313",
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