# CVE-2026-55377: Logto: Account Center MFA management step-up bypass via WebAuthn registration verification

> Attackers can bypass MFA step-up checks in Logto's Account Center to manage MFA factors without proving possession of existing credentials.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 10 Jul 2026
- **Updated:** 13 Jul 2026
- **Also known as:** GHSA-q4h3-38gc-4p4j

## What is CVE-2026-55377?

CVE-2026-55377 is a high-severity authentication bypass vulnerability in logto-io logto, published on 10 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

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.

Weakness: CWE-287 (Improper Authentication)

## Which versions are affected by CVE-2026-55377?


## How do I fix CVE-2026-55377?

No fix has been published for CVE-2026-55377 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-55377 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55377 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-55377 and fix it if it is affected.

What it is: CVE-2026-55377 is a high-severity authentication bypass vulnerability in logto-io logto, published on 10 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55377 exists.

Affected product: logto-io logto. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-55377/ (Markdown: https://insights.sbomify.com/CVE-2026-55377/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-55377
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-55377
- OSV: https://osv.dev/vulnerability/CVE-2026-55377

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-55377/
Summaries are generated and may contain mistakes; the official description above is the record.