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
- Version: 3.1
- Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
- Base score: 5.7
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.69%
- Percentile among all scored CVEs: 51
- Score date: 10/7/2026
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
- CWE-610
References
Raw JSON (NVD)
Show
{
"id": "CVE-2023-35838",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2023-35838",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2024-10-18T19:01:55.378972Z"
}
}
],
"cvssMetricV31": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 5.7,
"attackVector": "ADJACENT_NETWORK",
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "REQUIRED",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 2.1
}
]
},
"affected": [
{
"source": "cve@mitre.org",
"affectedData": [
{
"vendor": "n/a",
"product": "n/a",
"versions": [
{
"status": "affected",
"version": "n/a"
}
]
}
]
}
],
"published": "2023-08-09T23:15:10.007",
"references": [
{
"url": "https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2023-0015",
"source": "cve@mitre.org"
},
{
"url": "https://tunnelcrack.mathyvanhoef.com/details.html",
"tags": [
"Exploit",
"Third Party Advisory"
],
"source": "cve@mitre.org"
},
{
"url": "https://wireguard.com",
"tags": [
"Product"
],
"source": "cve@mitre.org"
},
{
"url": "https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2023-0015",
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://tunnelcrack.mathyvanhoef.com/details.html",
"tags": [
"Exploit",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://wireguard.com",
"tags": [
"Product"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-610"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "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."
}
],
"lastModified": "2026-06-17T06:05:18.313",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:wireguard:wireguard:0.5.3:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "20B2F68C-BAD1-4CA0-88B2-9AD317C88BC4"
}
],
"operator": "OR"
},
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:*",
"vulnerable": false,
"matchCriteriaId": "A2572D17-1DE6-457B-99CC-64AFD54487EA"
}
],
"operator": "OR"
}
],
"operator": "AND"
}
],
"sourceIdentifier": "cve@mitre.org"
}