Vulnerability identifier: #VU71431

Vulnerability risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2023-0056

CWE-ID: CWE-20

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 perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input within the http_wait_for_response() function when handling HTTP/2 requests. A remote attacker can send a specially crafted HTTP request the proxy server and perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

HAProxy: 2.0.0 - 2.0.30, 2.4.0 - 2.4.20, 2.2.0 - 2.2.26, 2.5.1 - 2.5.10, 2.7.0, 2.6.0 - 2.6.7, 2.3.0 - 2.3.21, 2.1.0 - 2.1.12

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External links
http://github.com/haproxy/haproxy/issues/1972

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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.