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Low severity3.7NVD Advisory· Published Apr 17, 2026· Updated Apr 17, 2026

CVE-2026-40263

CVE-2026-40263

Description

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.

Affected packages

Versions sourced from the GitHub Security Advisory.

PackageAffected versionsPatched versions
github.com/enchant97/note-mark/backendGo
< 0.19.2-0.20260411145025-cf4c6f6acf700.19.2-0.20260411145025-cf4c6f6acf70

Affected products

1

Patches

1
cf4c6f6acf70

(backend) prevent CWE-208 for internal login

https://github.com/enchant97/note-markLeo SprattApr 10, 2026via ghsa
commit
2 files changed · +9 −2
  • backend/db/models.go+8 −2 modified
    @@ -33,6 +33,8 @@ type User struct {
 	OidcRegistrations []OidcUser `gorm:"foreignKey:UserID" json:"oidcRegistrations,omitempty"`
 }
 
+var nullPasswordHash, _ = bcrypt.GenerateFromPassword([]byte("null"), bcrypt.DefaultCost)
+
 func (u *User) SetPassword(newPlainPassword string) {
 	hashedPw, err := bcrypt.GenerateFromPassword([]byte(newPlainPassword), bcrypt.DefaultCost)
 	if err != nil {
@@ -42,10 +44,14 @@ func (u *User) SetPassword(newPlainPassword string) {
 }
 
 func (u *User) IsPasswordMatch(plainPassword string) bool {
+	var current []byte
 	if len(u.Password) == 0 {
-		return false
+		// prevent CWE-208
+		current = nullPasswordHash
+	} else {
+		current = u.Password
 	}
-	if err := bcrypt.CompareHashAndPassword(u.Password, []byte(plainPassword)); err == nil {
+	if err := bcrypt.CompareHashAndPassword(current, []byte(plainPassword)); err == nil {
 		return true
 	}
 	return false
  • backend/services/auth.go+1 −0 modified
    @@ -29,6 +29,7 @@ func (s AuthService) GetAccessToken(
 	if err := db.DB.
 		First(&user, "username = ?", username).
 		Select("id", "password").Error; err != nil {
+		user.IsPasswordMatch(password) // prevent CWE-208
 		return core.AccessToken{}, InvalidCredentialsError
 	}

Vulnerability mechanics

Generated by null/stub on May 9, 2026. Inputs: CWE entries + fix-commit diffs from this CVE's patches. Citations validated against bundle.

References

4

News mentions

0

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