CVE-2026-41571
CRITICALCVE-2026-41571 is a critical-severity (CVSS 9.4) vulnerability in github.com/enchant97/note-mark/backend. O3 Security confirms whether CVE-2026-41571 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Note Mark: OIDC-registered users authenticated by submitting password "null"
Blast Radius
github.com/enchant97/note-mark/backendReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Note Mark is an open-source note-taking application. In version 0.19.2, IsPasswordMatch in backend/db/models.go falls back to a hard-coded bcrypt("null") placeholder whenever a user has no stored password. OIDC-registered users are created with an empty password, so anyone who submits password: "null" to the internal login endpoint receives a valid session for that user. The bypass is unauthenticated and requires no user interaction. This issue has been patched in version 0.19.3.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/enchant97/note-mark/backend | all versions | 0.0.0-20260417132909-dea5530cc989 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/enchant97/note-mark/backend. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/enchant97/note-mark/backend to 0.0.0-20260417132909-dea5530cc989 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-41571 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-41571 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-41571. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-41571 in your dependencies?
O3 detects CVE-2026-41571 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.