EspoCRM up to 9.1.6 Router Cache request smuggling

Summaryinfo

A vulnerability categorized as problematic has been discovered in EspoCRM up to 9.1.6. The impacted element is an unknown function of the component Router Cache. The manipulation results in request smuggling. This vulnerability is reported as CVE-2025-52892. The attack can be launched remotely. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in EspoCRM up to 9.1.6. It has been classified as problematic. Affected is an unknown functionality of the component Router Cache. 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 confidentiality, integrity, and availability. CVE summarizes:

EspoCRM is a web application with a frontend designed as a single-page application and a REST API backend written in PHP. In versions 9.1.6 and below, if a user loads Espo in the browser with double slashes (e.g https://domain//#Admin) and the webserver does not strip the double slash, it can cause a corrupted Slim router's cache. This will make the instance unusable until there is a completed rebuild. This is fixed in version 9.1.7.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2025-52892 since 06/20/2025. The exploitability is told to be easy. It is possible to launch the attack remotely. Additional levels of successful authentication are required for exploitation. There are neither technical details nor an exploit publicly available.

Upgrading to version 9.1.7 eliminates this vulnerability. Applying the patch 929611f317ce8892ea75873b0ab3094c0c510ff3 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

• EspoCRM

Version

• 9.1.0
• 9.1.1
• 9.1.2
• 9.1.3
• 9.1.4
• 9.1.5
• 9.1.6

License

• open-source

Website

• Product: https://github.com/espocrm/espocrm/

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Once again VulDB remains the best source for vulnerability data.

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