CVE-2023-43644

Name: CVE-2023-43644
Creator: NVD / NIST
Published: 2023-09-25T20:15:11.977+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 0.68%

Last modified Jun 17, 2026

CVE-2023-43644 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. Sing-box is an open source proxy system. Affected versions are subject to an authentication bypass when specially crafted requests are sent to sing-box. EPSS estimates a 0.68% chance of exploitation in the next 30 days.

Description

Sing-box is an open source proxy system. Affected versions are subject to an authentication bypass when specially crafted requests are sent to sing-box. This affects all SOCKS5 inbounds with user authentication and an attacker may be able to bypass authentication. Users are advised to update to sing-box 1.4.4 or to 1.5.0-rc.4. Users unable to update should not expose the SOCKS5 inbound to insecure environments.

Metrics

CVSS 3.1

9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

0.68%

47.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-306

Affected Software

Vendor	Product	Versions	Update
Sagernet	Sing-Box	< 1.4.5	—
Sagernet	Sing-Box	1.5.0	Beta1

References

https://github.com/SagerNet/sing-box/security/advisories/GHSA-r5hm-mp3j-285gVendor Advisory
https://github.com/SagerNet/sing-box/security/advisories/GHSA-r5hm-mp3j-285gVendor Advisory

Timeline

Published: Sep 25, 2023
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2023-43644?

How severe is CVE-2023-43644?

CVE-2023-43644 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 0.68% probability of exploitation in the next 30 days.

How do I fix CVE-2023-43644?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2023-43644?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST