UpTrain AI up to 0.7.1 Backend uptrain-access-token cross-domain policy

Summaryinfo

A vulnerability identified as problematic has been detected in UpTrain AI UpTrain up to 0.7.1. Affected by this issue is some unknown functionality of the component Backend. The manipulation of the argument uptrain-access-token leads to cross-domain policy. This vulnerability is uniquely identified as CVE-2025-27621. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in UpTrain AI UpTrain up to 0.7.1. It has been rated as problematic. This issue affects some unknown functionality of the component Backend. The manipulation of the argument uptrain-access-token with an unknown input leads to a cross-domain policy vulnerability. Using CWE to declare the problem leads to CWE-942. The product uses a cross-domain policy file that includes domains that should not be trusted. Impacted is confidentiality. The summary by CVE is:

UpTrain is an open-source platform to evaluate and improve generative AI applications. In version 0.7.1 and prior, the UpTrain backend creates a new default user with a static username, where the username is also used as the default API key. The UpTrain backend also has an open CORS policy. Using these two primitives, any website can make a authenticated cross-origin request to the UpTrain instance by providing the default API key in the header `uptrain-access-token`. This issue may allow arbitrary websites to perform privileged operations on the UpTrain instance, as if they were the default logged in user. As of time of publication, no known patches are available.

The advisory is shared at securitylab.github.com. The identification of this vulnerability is CVE-2025-27621 since 03/03/2025. The exploitation is known to be difficult. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 08/17/2026).

It is declared as proof-of-concept.

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

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

Productinfo

Type

• Artificial Intelligence Software

Vendor

• UpTrain AI

Name

• UpTrain

Version

• 0.7.0
• 0.7.1

CPE 2.3info

• 🔒
• 🔒

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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