CVE-2023-43644
Improper authentication in the SOCKS5 inbound in sing-box
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Improper authentication in the SOCKS5 inbound in sing-box
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.
- Record
CVE-2023-43644- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H - Weakness
- CWE-306
- Updated
- 2026-11-02
EUVDEUVD-2023-2582
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.
- Record
EUVD-2023-2582- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-r5hm-mp3j-285g
sing-box vulnerable to improper authentication in the SOCKS inbound
Impact
This vulnerability allows specially crafted requests to bypass authentication, affecting all SOCKS inbounds with user authentication.
Patches
Update to sing-box 1.4.5 or 1.5.0-rc.5 and later versions.
Workarounds
Don't expose the SOCKS5 inbound to insecure environments.
- Record
GHSA-r5hm-mp3j-285g- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H - Weakness
- CWE-306
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2023-43644- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-306
- Updated
- 2026-11-02
OSV
Improper authentication in the SOCKS5 inbound in sing-box
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.
- Record
CVE-2023-43644- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H - Weakness
- CWE-306
- Updated
- 2026-11-02
OSVGHSA-r5hm-mp3j-285g
sing-box vulnerable to improper authentication in the SOCKS inbound
Impact
This vulnerability allows specially crafted requests to bypass authentication, affecting all SOCKS inbounds with user authentication.
Patches
Update to sing-box 1.4.5 or 1.5.0-rc.5 and later versions.
Workarounds
Don't expose the SOCKS5 inbound to insecure environments.
- Record
GHSA-r5hm-mp3j-285g- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H - Weakness
- CWE-306
- Updated
- 2026-11-02
OSVGO-2023-2077No score
Authentication bypass in github.com/sagernet/sing
Authentication bypass in github.com/sagernet/sing
- Record
GO-2023-2077- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
github.com/sagernet/sing-boxGo | before 1.4.5 | 1.4.5 |
github.com/sagernet/sing-boxGo | 1.5.0-beta.1 up to 1.5.0-rc.5 | 1.5.0-rc.5 |
github.com/sagernet/singGo | before 0.2.12-0.20230925092853-5b05b5c147d9 | 0.2.12-0.20230925092853-5b05b5c147d9 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2023-43644 is a critical vulnerability (CVSS 9.1) in Sagernet Sing-box, published September 25, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.82%, the 57th percentile. Fixed in github.com/sagernet/sing-box 1.4.5.
References
github.com/SagerNet/sing-box/security/advisories/GHSA-r5hm-mp3j-285g
nvd.nist.gov/vuln/detail/CVE-2023-43644