CVE-2026-41571
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedNote 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.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceThe IsPasswordMatch function in Note Mark 0.19.2 contains an authentication bypass where it defaults to a hard-coded bcrypt hash of the string 'null' when a user has no stored password. OIDC-registered users are provisioned with empty passwords, making them vulnerable to anyone who authenticates with password:'null' against the login endpoint, granting unauthorized session access.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- Low
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify installed Note Mark versionCheck the application's version by reviewing the binary, release notes, or querying the application's version endpoint if available. Common locations: --version flag, about page, or metadata files in the installation directory.Affected if The installed version is 0.19.2 exactly, or falls within the range 0.19.0 to 0.19.2 inclusive.
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Confirm OIDC authentication is configuredReview the Note Mark configuration file (typically config.yaml, config.json, or environment variables) for OIDC provider settings such as OIDC_ISSUER, OIDC_CLIENT_ID, OIDC_CLIENT_SECRET, or similar OIDC-related parameters.Affected if OIDC authentication is enabled and configured, which results in users being created with empty password fields.
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Inspect database for users with empty passwordsQuery the database (likely a SQLite, PostgreSQL, or MySQL database) for user records where the password_hash or password field is empty, null, or unset. The table is typically named 'users' in the backend/db/models.go schema.Affected if Any user records exist with empty or null password fields, indicating they are vulnerable to the 'null' password bypass.
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Verify IsPasswordMatch function behaviorIf source code access is available, review backend/db/models.go and locate the IsPasswordMatch function. Check for hardcoded bcrypt hash comparisons or fallback logic that handles empty/null passwords.Affected if The function contains a fallback bcrypt comparison using a hardcoded hash (particularly bcrypt("null")) for users without stored passwords.
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Test authentication with null passwordSend a POST request to the login endpoint with a payload containing an OIDC user's identifier and password set to the literal string 'null' (for example: {"username": "<user>", "password": "null"}).Affected if The authentication succeeds and returns a valid session token, confirming the vulnerability is exploitable.
A user is affected if they run Note Mark version 0.19.2 (or any 0.19.x version prior to 0.19.3), have OIDC authentication enabled, and have users with empty password fields in the database.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scopedUpgrade to Note Mark version 0.19.3 or later to patch the vulnerable IsPasswordMatch function. Additionally, audit OIDC-provisioned user accounts and invalidate any sessions potentially obtained through this bypass.
0.19.3
- Upgrade Note Mark from version 0.19.2 to version 0.19.3 or later
- Verify the application version after upgrade to confirm the fix is applied
- Test OIDC login functionality to ensure it works correctly post-upgrade
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation1.0 h
- Testing4.0 h
- Review / QA2.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-41571 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-41571 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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