#VU96822 Infinite loop in HAProxy - CVE-2024-45506

Vulnerability identifier: #VU96822

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2024-45506

CWE-ID: CWE-835

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 infinite loop within the h2_send() function when zero-copy forwarding for HTTP/2 is enabled. A remote attacker can consume all available system resources and cause denial of service conditions.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

HAProxy: 2.9.0 - 2.9.9, 3.0.0 - 3.0.3

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External links
https://www.haproxy.org/download/3.1/src/CHANGELOG
https://www.mail-archive.com/haproxy%40formilux.org/msg45281.html
https://www.mail-archive.com/haproxy%40formilux.org/msg45280.html
https://git.haproxy.org/?p=haproxy-3.0.git%3Ba=commitdiff%3Bh=c725db17e8416ffb3c1537aea756356228ce5e3c
https://git.haproxy.org/?p=haproxy-3.0.git%3Ba=commitdiff%3Bh=d636e515453320c6e122c313c661a8ac7d387c7f

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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.