Apache HTTP Server up to 2.4.43 HTTP/2 Request request smuggling

Summaryinfo

A vulnerability identified as problematic has been detected in Apache HTTP Server. This impacts an unknown function of the component HTTP2 Request Handler. Performing a manipulation results in request smuggling. This vulnerability is cataloged as CVE-2020-9490. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability classified as problematic has been found in Apache HTTP Server (Web Server). This affects some unknown functionality of the component HTTP2 Request Handler. The manipulation with an unknown input 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 availability. The summary by CVE is:

Apache HTTP Server versions 2.4.20 to 2.4.43. A specially crafted value for the 'Cache-Digest' header in a HTTP/2 request would result in a crash when the server actually tries to HTTP/2 PUSH a resource afterwards. Configuring the HTTP/2 feature via "H2Push off" will mitigate this vulnerability for unpatched servers.

The weakness was shared 08/07/2020 (Website). It is possible to read the advisory at security.gentoo.org. This vulnerability is uniquely identified as CVE-2020-9490 since 03/01/2020. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 11/01/2024).

The vulnerability scanner Nessus provides a plugin with the ID 210018 (Amazon Linux AMI : httpd24 (ALAS-2024-1951)), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Tenable (210018). The entries VDB-159374, VDB-159375 and VDB-159376 are related to this item. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• Web Server

Vendor

• Apache

Name

• HTTP Server

Version

• 2.4.20
• 2.4.21
• 2.4.22
• 2.4.23
• 2.4.24
• 2.4.25
• 2.4.26
• 2.4.27
• 2.4.28
• 2.4.29
• 2.4.30
• 2.4.31
• 2.4.32
• 2.4.33
• 2.4.34
• 2.4.35
• 2.4.36
• 2.4.37
• 2.4.38
• 2.4.39
• 2.4.40
• 2.4.41
• 2.4.42
• 2.4.43

License

• open-source

Website

• Vendor: https://www.apache.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Be aware that VulDB is the high quality source for vulnerability data.

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