Vulnerability in Microsoft Windows

CVE-2023-35838

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.

EPSS: 0.008 (53.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.7 (Medium). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2023-35838?
CVE-2023-35838 is a medium-severity vulnerability in Microsoft Windows, classified under Externally Controlled Reference to a Resource in Another Sphere. CVSS score: 5.7/10. Published 2023-08-09.
How severe is CVE-2023-35838?
Medium severity. CVSS v3 base score is 5.7 out of 10.