Non-constant-time comparison when comparing hashes in Gradio

Vulnerability Description

Gradio is an open-source Python package designed for quick prototyping. This vulnerability involves a **timing attack** in the way Gradio compares hashes for the `analytics_dashboard` function. Since the comparison is not done in constant time, an attacker could exploit this by measuring the response time of different requests to infer the correct hash byte-by-byte. This can lead to unauthorized access to the analytics dashboard, especially if the attacker can repeatedly query the system with different keys. Users are advised to upgrade to `gradio>4.44` to mitigate this issue. To mitigate the risk before applying the patch, developers can manually patch the `analytics_dashboard` dashboard to use a **constant-time comparison** function for comparing sensitive values, such as hashes. Alternatively, access to the analytics dashboard can be disabled.

References

• https://github.com/gradio-app/gradio/security/advisories/GHSA-j757-pf57-f8r4