CVE-2026-93955
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.
What this means for your business
- An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.4% chance of attack attempts being seen in the next 30 days, ranking above 33% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 4.3 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N- CVSS v4
- 2.1
- Weakness
- CWE-285
- Assigned by
- cna@vuldb.com
Dates
- Published
- 2026-09-19
- Last modified
- 2026-09-21
- Sources
- NVD
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