CVE-2023-36673

Public Exploit

Description

An issue was discovered in Avira Phantom VPN through 2.23.1 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, while simultaneously using plaintext DNS to look up the VPN server's IP address. This allows an adversary to trick the victim into sending traffic to arbitrary IP addresses in plaintext outside the VPN tunnel. NOTE: the tunnelcrack.mathyvanhoef.com website uses this CVE ID to refer more generally to "ServerIP attack, combined with DNS spoofing, that can leak traffic to an arbitrary IP address" rather than to only Avira Phantom VPN.

Category

7.3
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.04%
Third-Party Advisory mathyvanhoef.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://www.avira.com/en/free-vpn product
https://tunnelcrack.mathyvanhoef.com/details.html third party advisory exploit
https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2023-0015

Frequently Asked Questions

What is the severity of CVE-2023-36673?
CVE-2023-36673 has been scored as a high severity vulnerability.
How to fix CVE-2023-36673?
To fix CVE-2023-36673, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-36673 being actively exploited in the wild?
It is possible that CVE-2023-36673 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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