Vulnerability identifier: #VU74299

Vulnerability risk: Low

CVSSv3.1: 3.5 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:N/E:U/RL:O/RC:C]

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

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External links
http://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.