# CVE-2026-126815: Pre-account hijacking via planted password

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

Pre-account hijacking in the authentication flow in Lagarto Chivato 0.4.1 and earlier on Web allows remote unauthenticated attackers to take over arbitrary accounts via a password planted on an unregistered email address that becomes valid upon the victim’s first passwordless login.

## Remediation

- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: Grayback) — https://www.grayback.es/advisories
- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: Grayback) — https://www.grayback.es/en/advisories

## Affected products and versions

- XauenDevs / Lagarto Chivato: ≥ 0.1.0; ≤ 0.4.2 (affected, custom); 0.4.4 (unaffected). Source: CNA: Grayback

## Severity and prioritization

- CVSS 3.1: 8.1 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N; source: CNA: Grayback

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-287

## Exploit evidence

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

## References

- https://www.grayback.es/advisories (CNA: Grayback; patch)

- https://www.grayback.es/en/advisories (CNA: Grayback; patch)

## Provenance

- CNA: Grayback: https://www.cve.org/CVERecord?id=CVE-2026-126815; retrieved 2026-11-11; source updated 2026-11-11

Revision: cf750077276c52a21243a5b5a5c8fbecad9ce2500ba1b0ffe180cd116400f786

Canonical: https://y2.dev/cve/CVE-2026-126815

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