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.

CVSS v3 4.3 MEDIUM
CVSS v2.0 4.0 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

4.0^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:L/Au:S/C:P/I:N/A:N

Exploitability : 8.0 / Impact : 2.9

Access Vector NETWORK

Access Complexity LOW

Authentication SINGLE

Confidentiality Impact PARTIAL

Integrity Impact NONE

Availability Impact NONE

References

Link	Resource
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

Configurations

No configuration.

History

21 Sep 2026, 21:17

Type	Values Removed	Values Added
References	~~() https://github.com/grimmory-tools/grimmory/issues/2431#issuecomment-5384402858 -~~	() https://github.com/grimmory-tools/grimmory/issues/2431#issuecomment-5384402858 -

19 Sep 2026, 23:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-19 23:17

Updated : 2026-09-21 21:17

NVD link : CVE-2026-93955

Mitre link : CVE-2026-93955

CVE.ORG link : CVE-2026-93955

JSON object : View

Products Affected

No product.

CWE

CWE-285

Improper Authorization

CWE-639

Authorization Bypass Through User-Controlled Key

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