Vpn
CVE-2023-36671
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A04:2025 - Cryptographic Failures
ASVS 5.0
V12 - Secure Communication Transport encryption
|
| Impact | CVSS score of 6.3 (MEDIUM). Attack characteristics: local attack vector, high complexity, no privileges required, user interaction required. Public proof-of-concept exploit code is available. |
| Exploit ScenarioDerived | Successful exploitation could compromise the medium-severity affected system. |
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Alert meAnalysisAI
An issue was discovered in the Clario VPN client through 5.9.1.1662 for macOS. Rated medium severity (CVSS 6.3), this vulnerability is no authentication required. Public exploit code available and no vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
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Technical ContextAI · show details
This vulnerability is classified under CWE-319. An issue was discovered in the Clario VPN client through 5.9.1.1662 for macOS. The VPN client insecurely configures the operating system such that all IP traffic to the VPN server's IP address is sent in plaintext outside the VPN tunnel even if this traffic is not generated by the VPN client. This allows an adversary to trick the victim into sending plaintext traffic to the VPN server's IP address and thereby deanonymize the victim. NOTE: the tunnelcrack.mathyvanhoef.com website uses this CVE ID to refer more generally to "ServerIP attack for only traffic to the real IP address of the VPN server" rather than to only Clario. Affected products include: Clario Vpn. Version information: through 5.9.1.1662.
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Severity by source
AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
An issue was discovered in the Clario VPN client through 5.9.1.1662 for macOS. The VPN client insecurely configures the operating system such that all IP traffic to the VPN server's IP address is sent in plaintext outside the VPN tunnel even if this traffic is not generated by the VPN client. This allows an adversary to trick the victim into sending plaintext traffic to the VPN server's IP address and thereby deanonymize the victim. NOTE: the tunnelcrack.mathyvanhoef.com website uses this CVE ID to refer more generally to "ServerIP attack for only traffic to the real IP address of the VPN server" rather than to only Clario.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.
Affected Products (CPE)NVD
SoftEtherVPN 5.02.5187 is vulnerable to Use after Free in the Command.c file via the CheckNetworkAcceptThread function.
SoftEther VPN 5.02.5187 is vulnerable to Buffer Overflow in the Command.c file via the PtMakeCert and PtMakeCert2048 fun
SoftEther VPN 5.02.5187 is vulnerable to Buffer Overflow in Internat.c via the UniToStrForSingleChars function. Rated cr
A heap-based buffer overflow vulnerability exists in the vpnserver WpcParsePacket() functionality of SoftEther VPN 4.41-
Hola VPN 1.34 has weak permissions (Everyone:F) under %PROGRAMFILES%, which allows local users to gain privileges via a
An authentication bypass vulnerability exists in the CiRpcAccepted() functionality of SoftEther VPN 4.41-9782-beta and 5
A denial-of-service vulnerability exists in the vpnserver ConnectionAccept() functionality of SoftEther VPN 5.02. Rated
A denial-of-service vulnerability exists in the vpnserver EnSafeHttpHeaderValueStr functionality of SoftEther VPN 5.01.9
An integer underflow vulnerability exists in the vpnserver OvsProcessData functionality of SoftEther VPN 5.01.9674 and 5
An authentication bypass vulnerability exists in the CiRpcServerThread() functionality of SoftEther VPN 5.01.9674 and 4.
A denial of service vulnerability exists in the DCRegister DDNS_RPC_MAX_RECV_SIZE functionality of SoftEther VPN 4.41-97
An issue was discovered in the Clario VPN client through 5.9.1.1662 for macOS. Rated medium severity (CVSS 5.7), this vu
NVD
CVE.org
EPSS
GitHub PoC
Exploit-DB