CVE-2026-93955

MEDIUMPre-NVD 4.34.3
EchelonGraph scoreLOW confidence

This medium-severity CVE scores 4.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit-prediction score not yet available (the EPSS model rescores nightly; freshly-published CVEs typically appear within 48 hours). GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: secondary
Trending — 4 sources updated this week
4.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 4.3Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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
EG Score
4.3(low)
EG Risk
24(Track)
EG Risk 24/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity43% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
34%
KEV
Not listed

Published

September 19, 2026

Last Modified

September 19, 2026

Advisory Details (3)

Auto-updated Sep 19, 2026
No patch confirmed yet.
generic

GitHub - grimmory-tools/grimmory: A self-hosted library for your ebooks, comics, and audiobooks · GitHub

https://github.com/grimmory-tools/grimmory/
generic

Kobo download endpoint lacks library access control (CWE-639) · Issue #2431 · grimmory-tools/grimmory · GitHub

https://github.com/grimmory-tools/grimmory/issues/2431#issuecomment-5384402858
generic

Kobo download endpoint lacks library access control (CWE-639) · Issue #2431 · grimmory-tools/grimmory · GitHub

https://github.com/grimmory-tools/grimmory/issues/2431

Vendor Advisories for CVE-2026-93955(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 5× in last 7d / 5× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-20 20:16 UTCEPSS rescore
  2. 2026-09-19 23:27 UTCEG score recompute
  3. 2026-09-19 23:27 UTCNVD updateCVSS v4 → 2.1
  4. 2026-09-19 22:21 UTCEG score recompute
  5. 2026-09-19 22:20 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-93955?
CVE-2026-93955 is a medium vulnerability published on September 19, 2026. 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…
When was CVE-2026-93955 disclosed?
CVE-2026-93955 was first published in the National Vulnerability Database on September 19, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-93955 actively exploited?
CVE-2026-93955 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 66.4% of all scored CVEs.
What is the CVSS score of CVE-2026-93955?
CVE-2026-93955 has a CVSS v3 base score of 4.3 (NVD). The EG score is currently aggregating — additional source signals are being incorporated as they become available..
How do I remediate CVE-2026-93955?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-93955, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-93955

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