CVE-2026-93955grimmory-tools grimmory Download Endpoint KoboController.java streamFileToResponse authorization
- 5.3MediumCVSS base score
- 0.41%Exploitation in 30 daysEPSS · top 64% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
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.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. 2 references of the record are tagged as an exploit. CISA's SSVC rates its exploitation: a proof of concept is public.
Show the exploits2
References tagged exploit2 references
Timeline
ID reserved
By VulDB
Published
- 2 days later
· 2 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| VulDBCNA (assigner) | 4.0 | Medium5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P |
| VulDBCNA (assigner) | 3.1 | Medium4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N/E:P/RL:X/RC:R |
| VulDBCNA (assigner) | 3.0 | Medium4.3 | CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N/E:P/RL:X/RC:R |
| VulDBCNA (assigner) | 2.0 | Medium4.0 | AV:N/AC:L/Au:S/C:P/I:N/A:N/E:POC/RL:ND/RC:C |
| NVDNVD · Deferred | 4.0 | Low2.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 0.41% · top 64% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.3.
Affected products
- affected 3.3.0
- affected 3.3.1
- affected 3.3.2
- affected 3.3.3
- affected 3.4.0
- affected 3.4.1
References
References7
- VDB-407914 | grimmory-tools grimmory Download Endpoint KoboController.java streamFileToResponse authorization (opens in a new tab)vdb-entrytechnical-description
- VDB-407914 | CTI Indicators (IOB, IOC, IOA) (opens in a new tab)signaturepermissions-required
- CVE-2026-93955 | CVE Analysis and Report (opens in a new tab)third-party-advisory
- Submit #943921 | grimmory-tools grimmory 3.3.3 Incorrect Access Control (opens in a new tab)third-party-advisory
- https://github.com/grimmory-tools/grimmory/issues/2431 (opens in a new tab)exploitissue-tracking
- https://github.com/grimmory-tools/grimmory/issues/2431#issuecomment-5384402858 (opens in a new tab)issue-trackingexploit
- https://github.com/grimmory-tools/grimmory/ (opens in a new tab)product
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-83611 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-93955)Record last updated .