CVE-2026-100679

stoatchat before 0.15.5 fails to validate that MFA tickets belong to the authenticated user, allowing attackers to bypass MFA by using their own valid ticket with another user's session token. Attackers can obtain a ticket from their own account and use it with a victim's session token to disable TOTP, view recovery codes, or perform other sensitive operations without providing the victim's credentials.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/stoatchat/stoatchat/security/advisories/GHSA-gwg6-q3c3-97cx
https://www.vulncheck.com/advisories/stoatchat-before-0.15.5-mfa-bypass-via-cross-account-ticket
https://github.com/stoatchat/stoatchat/security/advisories/GHSA-gwg6-q3c3-97cx

Configurations

No configuration.

History

28 Sep 2026, 18:17

Type	Values Removed	Values Added
References	~~() https://github.com/stoatchat/stoatchat/security/advisories/GHSA-gwg6-q3c3-97cx -~~	() https://github.com/stoatchat/stoatchat/security/advisories/GHSA-gwg6-q3c3-97cx -

26 Sep 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-26 14:16

Updated : 2026-09-28 18:17

NVD link : CVE-2026-100679

Mitre link : CVE-2026-100679

CVE.ORG link : CVE-2026-100679

JSON object : View

Products Affected

No product.

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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