CVE-2026-85237

What it is

A vulnerability in MISP's email-based one-time password (OTP) authentication flow allowed an attacker to perform an unrestricted number of OTP verification attempts. The email_otp() endpoint did not apply brute-force protection when validating submitted OTP values. An attacker who had reached the OTP verification stage, for example after successfully providing a user's primary authentication credentials, could repeatedly submit candidate OTP values while the same OTP remained valid. This significantly increased the feasibility of guessing the OTP and bypassing the additional authentication factor, potentially resulting in unauthorized access to the affected user's account. The issue was exacerbated by the fact that the OTP is associated with the user rather than with an individual pending login session, allowing multiple concurrent sessions to attempt guesses against the same valid OTP. The patch integrates the existing MISP brute-force protection mechanism into the email OTP flow. Failed OTP attempts are now counted against the user, further attempts are rejected once the configured threshold is reached, and the active OTP is invalidated when the attempt budget is exhausted. Blocklisted users are also prevented from requesting the generation of a fresh OTP. In addition, OTP comparison now uses hash_equals() and validates that the submitted value is a string.

At a glance

Exploitability

Can be exploited over the network with a low-privilege account. High risk of data exposure, data tampering.

Exploit odds

0.5% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-09-03 16:18 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-09-11 14:15 UTC Last updatedMost recent change to the record

Details

Published

2026-09-03 16:18 UTC

Last modified

2026-09-11 14:15 UTC

Exploit probability

0.5% · EPSS, next 30 days

Weakness

CWE-307

Record status

Analyzed

Affected

• misp-project Misp ≤ 2.5.45

Attack profile CVSS 4.0 · 8.6

Attack vector

Network

Complexity

Low

Attack requirements

None

Privileges needed

Low

User interaction

None

Confidentiality

High

Integrity

High

Availability

None