# CVE-2026-126257: CVE-2026-126257

Status: published. Published: 2026-11-11. Updated: 2026-11-11.

A use of hard-coded password vulnerability in Fortinet FortiAuthenticator 8.0.0 through 8.0.3, FortiAuthenticator 6.6.0 through 6.6.10 may allow an unauthenticated attacker to bypass credential validation in certain circumstances outside of the attacker's control and gain unauthorized access.

## Remediation

- fix: Upgrade to FortiAuthenticator version 8.0.4 or above
Upgrade to FortiAuthenticator version 6.6.11 or above (source: CNA: fortinet)

## Affected products and versions

- Fortinet / FortiAuthenticator: ≥ 8.0.0; ≤ 8.0.3 (affected, semver); ≥ 6.6.0; ≤ 6.6.10 (affected, semver). Source: CNA: fortinet

## Severity and prioritization

- CVSS 3.1: 9 (critical); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H/E:P/RL:O/RC:C; source: CNA: fortinet

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-259

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://fortiguard.fortinet.com/psirt/FG-IR-26-271 (CNA: fortinet)

## Provenance

- CNA: fortinet: https://www.cve.org/CVERecord?id=CVE-2026-126257; retrieved 2026-11-11; source updated 2026-11-11

Revision: 8a861e4e442d397db6f877e1c8968894c9b281ba20621a3ce528623fc3f40dac

Canonical: https://y2.dev/cve/CVE-2026-126257

## Agent and API access

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- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

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- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

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