pyload 0.5.0b3.dev88 CAPTCHA code injection

Summaryinfo

A vulnerability classified as critical has been found in pyload 0.5.0b3.dev88. Affected by this vulnerability is an unknown functionality of the component CAPTCHA Handler. Performing a manipulation results in code injection. This vulnerability is identified as CVE-2025-53890. The attack can be initiated remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in pyload 0.5.0b3.dev88. This affects some unknown processing of the component CAPTCHA Handler. The manipulation with an unknown input leads to a code injection vulnerability. CWE is classifying the issue as CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

pyload is an open-source Download Manager written in pure Python. An unsafe JavaScript evaluation vulnerability in pyLoad’s CAPTCHA processing code allows unauthenticated remote attackers to execute arbitrary code in the client browser and potentially the backend server. Exploitation requires no user interaction or authentication and can result in session hijacking, credential theft, and full system remote code execution. Commit 909e5c97885237530d1264cfceb5555870eb9546, the patch for the issue, is included in version 0.5.0b3.dev89.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2025-53890 since 07/11/2025. The exploitability is told to be easy. 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 attack technique deployed by this issue is T1059 according to MITRE ATT&CK.

Upgrading to version 0.5.0b3.dev89 eliminates this vulnerability. Applying the patch 909e5c97885237530d1264cfceb5555870eb9546 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.

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Productinfo

Name

• pyload

Version

• 0.5.0b3.dev88

License

• open-source

Website

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

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