What’s Vulnerable › Vulnerabilities

CVE-2026-93955: grimmory-tools grimmory Download Endpoint KoboController.java streamFileToResponse authorization

• Severity: medium (CVSS 4.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-19 · updated 2026-09-21
• Weakness: CWE-285

Description

A vulnerability was detected in grimmory-tools grimmory up to 3.3.3/3.4.1. Affected by this vulnerability is the function streamFileToResponse of the file backend/src/main/java/org/booklore/controller/KoboController.java of the component Download Endpoint. Performing a manipulation of the argument bookId results in authorization bypass. The attack may be initiated remotely. The exploit is now public and may be used. Issue #2431 is closed as completed, but its only comment states that the issue “has already been reported elsewhere.” No fixing commit or pull request is identified there.

Affected products

• grimmory-tools grimmory: 3.3.0, 3.3.1, 3.3.2, 3.3.3, 3.4.0, 3.4.1

References

• https://github.com/grimmory-tools/grimmory/
• https://github.com/grimmory-tools/grimmory/issues/2431
• https://github.com/grimmory-tools/grimmory/issues/2431#issuecomment-5384402858
• https://vuldb.com/cve/CVE-2026-93955
• https://vuldb.com/submit/943921
• https://vuldb.com/vuln/407914
• https://vuldb.com/vuln/407914/cti
• https://github.com/grimmory-tools/grimmory/issues/2431#issuecomment-5384402858

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