HAProxy up to 2.7.2 Header Field request smuggling

Summaryinfo

A vulnerability was found in HAProxy up to 2.7.2 and classified as critical. This affects an unknown part of the component Header Field Handler. Such manipulation leads to request smuggling. This vulnerability is documented as CVE-2023-25725. The attack can be executed remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in HAProxy up to 2.7.2 (Firewall Software) and classified as critical. Affected by this issue is an unknown code of the component Header Field Handler. The manipulation with an unknown input leads to a request smuggling vulnerability. Using CWE to declare the problem leads to CWE-444. The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination. Impacted is confidentiality, integrity, and availability. CVE summarizes:

HAProxy before 2.7.3 may allow a bypass of access control because HTTP/1 headers are inadvertently lost in some situations, aka "request smuggling." The HTTP header parsers in HAProxy may accept empty header field names, which could be used to truncate the list of HTTP headers and thus make some headers disappear after being parsed and processed for HTTP/1.0 and HTTP/1.1. For HTTP/2 and HTTP/3, the impact is limited because the headers disappear before being parsed and processed, as if they had not been sent by the client. The fixed versions are 2.7.3, 2.6.9, 2.5.12, 2.4.22, 2.2.29, and 2.0.31.

The weakness was released 02/14/2023. The advisory is shared for download at git.haproxy.org. This vulnerability is handled as CVE-2023-25725 since 02/13/2023. There are neither technical details nor an exploit publicly available.

Upgrading eliminates this vulnerability. Applying the patch a0e561ad7f29ed50c473f5a9da664267b60d1112 is able to eliminate this problem. The bugfix is ready for download at git.haproxy.org. The best possible mitigation is suggested to be upgrading to the latest version.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Firewall Software

Name

• HAProxy

Version

• 2.7.0
• 2.7.1
• 2.7.2

License

• open-source

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

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