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Vulnerability

CVE-2026-77561: Tinyauth is an authentication and authorization server. Prior to 5.1.0, an unauthenticated remote attacker can send POST /api/user/login requests with 257 distinct nonexistent usernames to fill MaxLoginAttemptRecords and

Official source
EudorIA operational summary

What it means

Priority 45/100

NIST National Vulnerability Database ha pubblicato CVE-2026-77561. La rilevanza va confermata rispetto alle tecnologie effettivamente in uso.

Why it matters

Il segnale diventa operativo solo se prodotto, versione o servizio sono presenti nel perimetro.

AudienceITSOCCISO
Information centre

Translation in progress

NIST National Vulnerability Database

The official content is available in the original language. The Italian version will be published once automated checks are complete.

Text acquired from the source

Tinyauth is an authentication and authorization server. Prior to 5.1.0, an unauthenticated remote attacker can send POST /api/user/login requests with 257 distinct nonexistent usernames to fill MaxLoginAttemptRecords and activate a global login lockdown. internal/controller/user_controller.go loginHandler passes each attacker-controlled identifier to internal/service/auth_service.go RecordLoginAttempt, which invokes lockdownMode after the map reaches its cap. IsAccountLocked checks that global state before validating unrelated accounts, causing valid users to receive HTTP 429 until auth.loginTimeout expires, approximately 300 seconds by default. The attack can be repeated, but existing authenticated sessions are not invalidated. This issue is fixed in version 5.1.0.

Source
NIST National Vulnerability Database
Publishing entity
NIST National Vulnerability Database
Entity type
National authority
Area
North America · US
Original language
en · translation in preparation
Publication
21/09/2026 19:18
CVE
CVE-2026-77561
Classification
Medium
Stated country
US
Technical scope

Affected products and versions

Not published
No structured range published.

The official sources queried do not yet expose a list of affected versions. No automatic inference is made.

Sources for the versionsNIST National Vulnerability Database
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