6.4
MEDIUM CVSS 3.1
CVE-2026-55370
Logto: TOTP code can be replayed within the RFC 6238 validity window (one-time use violation)
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.

INFO

Published Date :

July 10, 2026, 8:16 p.m.

Last Modified :

July 10, 2026, 9:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-55370 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 MEDIUM [email protected]
Solution
Update Logto to version 1.41.0 or later to fix TOTP replay vulnerability.
  • Update Logto to version 1.41.0 or later.
  • Ensure TOTP verification logic is robust.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-55370 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-55370 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-55370 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jul. 10, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-55370', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-07-10T20:14:33.407390Z'}
  • New CVE Received by [email protected]

    Jul. 10, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'logto-io', 'product': 'logto', 'versions': [{'status': 'affected', 'version': '< 1.41.0'}]}]
    Added 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.
    Added CVSS V3.1 AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N
    Added CWE CWE-294
    Added Reference https://github.com/logto-io/logto/commit/9118867f6cbadc7291cf913beb4fede91ed5d374
    Added Reference https://github.com/logto-io/logto/pull/9109
    Added Reference https://github.com/logto-io/logto/releases/tag/v1.41.0
    Added Reference https://github.com/logto-io/logto/security/advisories/GHSA-6wj7-c66m-6c82
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.