#VU74299 Memory leak in HAProxy - CVE-2023-0836

Vulnerability identifier: #VU74299

Vulnerability risk: Low

CVSSv4.0: 1.7 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2023-0836

CWE-ID: CWE-401

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
HAProxy
Server applications / IDS/IPS systems, Firewalls and proxy servers

Vendor: HAProxy

Description
The vulnerability allows a remote attacker to gain access to sensitive information.

The vulnerability exists due memory leak as there are 5 bytes left uninitialized in the connection buffer when encoding the FCGI_BEGIN_REQUEST record. A remote attacker can force the application to leak memory and disclose potentially sensitive data to configured FastCGI backends.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

HAProxy: 2.1.0 - 2.1.12, 2.2.0 - 2.2.26, 2.4.0 - 2.4.20, 2.5.0 - 2.5.10, 2.6.0 - 2.6.7, 2.7.0

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External links
https://git.haproxy.org/?p=haproxy.git;a=commitdiff;h=2e6bf0a

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.