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CVE-2026-40263

Note Mark: Username Enumeration via Login Endpoint Timing Side-Channel

Published: Apr 16, 2026Updated: Apr 17, 2026 Sources: CVE List NVD
NVD MITRE
3.7CVSS
LOW

Note Mark is an open-source note-taking application. In versions 0.19.1 and prior, the login endpoint performs bcrypt password verification only when the supplied username exists, returning immediately for nonexistent usernames. This timing discrepancy allows unauthenticated attackers to enumerate valid usernames by measuring response times, enabling targeted credential attacks. This issue has been fixed in version 0.19.2.

EPSS Score
N/A
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
No Fix Available

CVSS Vector Breakdown

AV:NAC:HPR:NUI:NS:UC:LI:NA:N
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:LConfidentiality
Low
I:NIntegrity
None
A:NAvailability
None

Weaknesses

CWE-208

Affected Products

note-mark
enchant97

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

References

https://github.com/enchant97/note-mark/security/advisories/GHSA-w6m9-39cv-2fwp
github.com
https://github.com/enchant97/note-mark/commit/cf4c6f6acf70b569d80396d323b067c00d45c034
github.com

Timeline

Published
Apr 16, 2026
Last Updated
Apr 17, 2026

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