CVE-2026-40265: Note Mark has Broken Access Control on Asset Download

CVE-2026-40265 · Severity: medium · CVSS 5.9 · Published 2026-04-17

Note Mark is an open-source note-taking application. In versions 0.19.1 and prior, the asset download endpoint at /api/notes/{noteID}/assets/{assetID} is registered without authentication middleware, and the backend query does not verify ownership or book visibility. An unauthenticated user who knows a valid note ID and asset ID can retrieve the full contents of private note assets without authentication, regardless of whether the associated book is public or private. This issue has been fixed in version 0.19.2.

Technologies: github.com/enchant97/note-mark/backend (Go). Vendors: Go.

Quick answers

Is CVE-2026-40265 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-40265 being exploited in the wild.
How severe is CVE-2026-40265?
Medium severity, with a CVSS score of 5.9, published 17 April 2026.
Which products and versions are affected?
github.com/enchant97/note-mark/backend (Go) < 0.0.0-20260411145023-6593898855ad, SEMVER:introduced=0,fixed=0.0.0-20260411145023-6593898855ad.
Is there a fix for CVE-2026-40265?
Yes. github.com/enchant97/note-mark/backend (Go): upgrade to 0.0.0-20260411145023-6593898855ad or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
Am I affected by CVE-2026-40265?
Check whether you run github.com/enchant97/note-mark/backend (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • github.com/enchant97/note-mark/backend (Go): upgrade to 0.0.0-20260411145023-6593898855ad or later
    go get github.com/enchant97/note-mark/backend@v0.0.0-20260411145023-6593898855ad

Affected products

  • github.com/enchant97/note-mark/backend (Go) < 0.0.0-20260411145023-6593898855ad, SEMVER:introduced=0,fixed=0.0.0-20260411145023-6593898855ad

Identifiers

  • CVE-2026-40265
  • GHSA-p5w6-75f9-cc2p
  • GO-2026-5530

References

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