CVE-2026-55377Public exploitNetwork attack vector

MFA step-up bypass via verification-purpose confusion

Published Jul 10, 2026 · Updated Jul 10, 2026

Improper authentication in Logto before 1.41.0 allows remote authenticated users to alter MFA factors through Account Center. koaOidcAuth accepts any verified, user-owned record named by the logto-verification-id header, even when the record proves only registration of a new WebAuthn credential rather than reauthentication. Exploitation requires a victim Account API bearer token with identity-management scopes and an editable MFA field, and permits adding attacker-controlled factors or deleting existing factors.

CVSS severity8.1
High
EPSS probability0.46%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Improper authentication in Logto before 1.41.0 allows remote authenticated users to alter MFA factors through Account Center. koaOidcAuth accepts any verified, user-owned record named by the logto-verification-id header, even when the record proves only registration of a new WebAuthn credential rather than reauthentication. Exploitation requires a victim Account API bearer token with identity-management scopes and an editable MFA field, and permits adding attacker-controlled factors or deleting existing factors.

The record

CVE
CVE-2026-55377
Published
Jul 10, 2026
Updated
Jul 10, 2026
Vendor
Logto
Product
Logto
Classifications
CWE-287, T1098.005
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 10, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 10, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 1.41.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Logto · Logtoversion=< 1.41.0

Published CVSS scores

8.1GitHubCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-287Improper Authentication
T1098.005Device Registration

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo