Apache Traffic Server up to 7.1.12/8.1.1/9.0.1 Cache request smuggling

Summaryinfo

A vulnerability classified as problematic has been found in Apache Traffic Server up to 7.1.12/8.1.1/9.0.1. This affects an unknown part of the component Cache Handler. Performing a manipulation results in request smuggling. This vulnerability is cataloged as CVE-2021-27577. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in Apache Traffic Server up to 7.1.12/8.1.1/9.0.1. It has been classified as problematic. This affects some unknown processing of the component Cache 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 integrity, and availability.

The weakness was shared 06/29/2021. The advisory is shared at lists.apache.org. This vulnerability is uniquely identified as CVE-2021-27577. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 08/27/2025).

The vulnerability scanner Nessus provides a plugin with the ID 256759 (Linux Distros Unpatched Vulnerability : CVE-2021-27577), 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 (256759). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• Apache

Name

• Traffic Server

Version

• 7.1.0
• 7.1.1
• 7.1.2
• 7.1.3
• 7.1.4
• 7.1.5
• 7.1.6
• 7.1.7
• 7.1.8
• 7.1.9
• 7.1.10
• 7.1.11
• 7.1.12
• 8.1.0
• 8.1.1
• 9.0.0
• 9.0.1

License

• open-source

Website

• Vendor: https://www.apache.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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