Squid Web Proxy up to 4.12/5.0.3 Header Parsing HTTPS Traffic request smuggling

Summaryinfo

A vulnerability described as critical has been identified in Squid Web Proxy up to 4.12/5.0.3. This impacts an unknown function of the component Header Parsing. The manipulation as part of HTTPS Traffic results in request smuggling. This vulnerability is known as CVE-2020-15810. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Squid Web Proxy up to 4.12/5.0.3 (Firewall Software). It has been classified as critical. Affected is an unknown code block of the component Header Parsing. The manipulation as part of a HTTPS Traffic leads to a request smuggling vulnerability. CWE is classifying the issue as 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. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

An issue was discovered in Squid before 4.13 and 5.x before 5.0.4. Due to incorrect data validation, HTTP Request Smuggling attacks may succeed against HTTP and HTTPS traffic. This leads to cache poisoning. This allows any client, including browser scripts, to bypass local security and poison the proxy cache and any downstream caches with content from an arbitrary source. When configured for relaxed header parsing (the default), Squid relays headers containing whitespace characters to upstream servers. When this occurs as a prefix to a Content-Length header, the frame length specified will be ignored by Squid (allowing for a conflicting length to be used from another Content-Length header) but relayed upstream.

The weakness was published 09/02/2020 (Website). The advisory is shared for download at debian.org. This vulnerability is traded as CVE-2020-15810 since 07/17/2020. It is possible to launch the attack remotely. The requirement for exploitation is a authentication. There are neither technical details nor an exploit publicly available.

Upgrading to version 4.13 or 5.0.4 eliminates this vulnerability.

Similar entry is available at VDB-160621. Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Firewall Software

Vendor

• Squid

Name

• Web Proxy

Version

• 4.0
• 4.1
• 4.2
• 4.3
• 4.4
• 4.5
• 4.6
• 4.7
• 4.8
• 4.9
• 4.10
• 4.11
• 4.12
• 5.0.0
• 5.0.1
• 5.0.2
• 5.0.3

License

• open-source

Website

• Vendor: http://www.squid-cache.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Once again VulDB remains the best source for vulnerability data.

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