CVE-2023-36671

Exp

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.

Published: 2023-08-09 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-36671 is rated Exploit Available (50/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.31%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2023-36671

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2023-36671

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.03% 0.31% +0.28%
2 2025-03-17 0.05% 0.03% -0.02%
3 2023-08-23 — 0.05% —

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-36671

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.3 3.1 MEDIUM
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 1.0 5.2 [email protected]

Weakness enumeration for CVE-2023-36671

OS Trackers for CVE-2023-36671

vendor priority summary link
ubuntu medium CVE-2023-36671 medium priority: Ubuntu including 31 source packages (connman, gadmin-openvpn-client, …), 341 status rows across 11 suites (bionic, focal, jammy, lunar, mantic, noble, oracular, plucky, trusty, upstream, xenial): not-affected 211, DNE 82, ignored 48. https://ubuntu.com/security/CVE-2023-36671

Affected software / configurations for CVE-2023-36671

Vendor Product Version Raw CPE
clario vpn <= 5.9.1.1662 cpe:2.3:a:clario:vpn:*:*:*:*:*:macos:*:*

References for CVE-2023-36671

cvelogic Threat Intelligence