Unrated severityNVD Advisory· Published Jul 10, 2026· Updated Jul 10, 2026
Logto: TOTP code can be replayed within the RFC 6238 validity window (one-time use violation)
CVE-2026-55370
Description
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.
Affected products
1Patches
Vulnerability mechanics
References
4- github.com/logto-io/logto/commit/9118867f6cbadc7291cf913beb4fede91ed5d374mitrex_refsource_MISC
- github.com/logto-io/logto/pull/9109mitrex_refsource_MISC
- github.com/logto-io/logto/releases/tag/v1.41.0mitrex_refsource_MISC
- github.com/logto-io/logto/security/advisories/GHSA-6wj7-c66m-6c82mitrex_refsource_CONFIRM
News mentions
0No linked articles in our index yet.