CVE-2026-103655: Authentication Bypass by Capture-replay

MISP contains a vulnerability in its two-factor authentication (TOTP) verification process that permits a valid one-time code to be accepted more than once within its time-based validity window.

The issue exists in the user login flow where a TOTP code is verified as a second authentication factor. Because the system did not record whether a given TOTP period had already been consumed, the same code remained valid for its entire time window (typically 30 seconds). An attacker who captures a legitimate code during a user's login could replay it to authenticate a second session as that user.

Preconditions:

- The target user has TOTP-based two-factor authentication enabled.

- The attacker is in a position to observe or intercept the TOTP code during a legitimate login (e.g., network-level interception, shoulder surfing, or a compromised client).

- The replay must occur within the TOTP validity period.

Security impact:

- Unauthorized account access by replaying a captured one-time code.

- Potential compromise of threat-intelligence data and administrative functions accessible to the targeted user.

Affected versions: <v2.5.48.