Auth bypass in Logto-Io Logto

CVE-2026-55377

Logto is the modern, open-source auth infrastructure for SaaS and AI apps. Prior to 1.41.0, Logto's Account Center step-up check accepted any active verification record that belonged to the current user and had isVerified === true. A WebAuthn registration verification record for binding a new passkey could be created and verified with only an existing Account API bearer token, then sent in the logto-verification-id header and treated as identityVerified=true by Account Center routes, allowing MFA factor management without proving possession of an existing password, identifier, or MFA factor. This issue is fixed in version 1.41.0.

Vulnerability class: Broken Authentication

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.005 (38.2th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 38th percentile — 38.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-55377: held from 0.005 to 0.005.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-55377?
CVE-2026-55377 is a high-severity vulnerability in Logto-Io Logto, classified under Improper Authentication. CVSS score: 8.1/10. Published 2026-07-10.
How severe is CVE-2026-55377?
High severity. CVSS v3 base score is 8.1 out of 10.