CVE-2026-55370: medium-severity vulnerability in logto-io logto
Logto: TOTP code can be replayed within the RFC 6238 validity window (one-time use violation)
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.4epss 0.3%
Logto is the modern, open-source auth infrastructure for SaaS and AI apps. Prior to 1.41.0, Logto's existing TOTP verification accepted a successfully used TOTP code again while the code remained inside the RFC 6238 acceptance window because the verifier used otplib's stateless check with window = 1 and did not persist or compare the accepted TOTP time-step counter. An attacker who has the victim's first factor and captures a live TOTP value can replay that value to satisfy MFA during the same acceptance window. This issue is fixed in version 1.41.0.
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N
Affected products
logto-io · logtoRelated CVEs — logto-io logto
In the same product, most dangerous first.
CVE-2026-62317HIGHLogto: ReDoS via unescaped user input in email subaddressing regex (blockSubaddressing)EPSS 0.7%CVE-2026-63188HIGHlogto-tunnel serves files outside --experience-path via path traversalEPSS 0.5%CVE-2026-82263HIGHLogto Server-Side Request Forgery via OIDC SSO Connector Issuer URLEPSS 0.5%CVE-2026-82262HIGHLogto Server-Side Request Forgery via webhook test endpointEPSS 0.5%CVE-2026-55377HIGHLogto: Account Center MFA management step-up bypass via WebAuthn registration verificationEPSS 0.4%CVE-2026-63187MEDIUMLogto: OS command injection vulnerability exists in the Commitlint workflowEPSS 0.4%