CVE-2026-85216
CriticalCVSS 9.5Summary
MISP contains an authentication bypass vulnerability in its LDAP and LinOTP authentication components due to insufficient validation of user-supplied credentials. An attacker knowing a valid directory user's email address could submit an empty password, which may be accepted by an LDAP server allowing unauthenticated binds. Additionally, in the LinOTP component, empty passwords could be checked against local MISP password hashes, and LDAP-provisioned accounts could be created with empty local passwords.
Risk Assessment
A remote unauthenticated attacker can impersonate an existing MISP user, including administrators, gaining access to sensitive threat-intelligence data, the ability to modify or delete information, alter configuration, or perform other privileged operations.
Recommendation
Apply the vendor-provided patch immediately, which enforces that authentication identifiers and passwords are valid strings, rejects empty passwords where not explicitly permitted, and assigns a randomly generated local password to LDAP-provisioned accounts. After updating, audit existing accounts for empty passwords.
Other vulnerabilities in MISP
See all- CVE-2026-85239High
A vulnerability in MISP allows an authenticated user with permission to create or modify event templates to bypass validation of the template definition field. By supplying a pre-encoded string instead of an array structure, an invalid definition can be persistently stored. On retrieval, invalid JSON triggers an exception, causing HTTP 500 errors in event template functionality.
- CVE-2026-85238High
MISP contains a session fixation vulnerability in the CustomAuth authentication flow. After successful authentication via CustomAuth, MISP stores the authenticated user identity in the existing session without first rotating the session identifier. An attacker who knows the victim's session identifier before authentication can later reuse it to access the victim's authenticated session.
- CVE-2026-85237High
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, enabling repeated guessing of OTP and potential bypass of the additional authentication factor.
- CVE-2026-85236High
A cross-site request forgery (CSRF) vulnerability existed in the cullEmptyEvents action of MISP. The endpoint performed a state-changing and irreversible operation while accepting HTTP GET requests. An attacker could cause an authenticated user with sufficient privileges to invoke the endpoint, leading to deletion of published empty events.
- CVE-2026-85227Medium
MISP contains a reflected Cross-Site Scripting (XSS) vulnerability in the event attribute filtering query builder. The taggedAttributes and galaxyAttachedAttributes URL parameters were inserted into the query-builder rules without HTML escaping before being serialized as JSON and embedded inside a <script> element.
- CVE-2026-85226Medium
MISP contains an authorization flaw in the OnDemand correlation engine where correlations were calculated solely from matching attribute values without applying the distribution, sharing group, organization, or other access-control restrictions associated with the correlated attributes and events. As a result, an authenticated user could receive correlation results referring to attributes or events that the user was not authorized to access.
- CVE-2026-61474Medium
An improper authorization check in MISP's attribute creation endpoint allowed an authenticated user with permission to add attributes to submit a sharing_group_id without triggering the corresponding sharing group authorization check, as long as the attribute distribution value was not explicitly set to 4 — 'sharing group'.
- CVE-2017-14337High
In MISP versions before 2.4.80, when configured with X.509 certificate authentication alongside a non-MISP external user management API, an unauthenticated user can gain access as an arbitrary user if the API returns an empty value.
- CVE-2026-10868Critical
MISP has a mass assignment vulnerability in the user edit functionality (UsersController::edit()). An authenticated attacker can modify the user ID in the request, leading to updates on another user's account.
- CVE-2026-10611Critical
MISP contains an authentication bypass vulnerability when LDAP mixed authentication is enabled with OTP enforcement. An authenticated user can bypass the OTP step and access the application without providing a TOTP, HOTP, or email OTP code.
Original NVD description (English source)
MISP contains an authentication bypass vulnerability in its LDAP and LinOTP authentication components due to insufficient validation of user-supplied credentials. The custom LdapAuthenticate and LinOTPAuthenticate components replace CakePHP's FormAuthenticate implementation but did not replicate its credential validation checks. As a result, empty or non-string values could reach the underlying authentication mechanisms. In the LDAP authentication path, an attacker able to identify a valid directory user's email address could submit an empty password. The empty credential could be passed to ldap_bind(), where an LDAP server accepting unauthenticated binds may return a successful result for a valid distinguished name combined with an empty password. MISP could consequently treat the attacker as the corresponding authenticated directory user without verification of the user's password. The issue also affected the LinOTP authentication component. Invalid credential types were not rejected before being processed, and when mixed authentication was enabled, an empty password could be checked against a locally stored MISP password hash. LDAP-provisioned MISP accounts could additionally be created with an empty local password because account creation skipped normal validation, resulting in a hash corresponding to an empty password. This could permit authentication through the local fallback mechanism when such an account was no longer resolved through LDAP. Successful exploitation could allow a remote unauthenticated attacker to impersonate an existing MISP user. If the targeted account has administrative or other privileged permissions, the attacker could gain corresponding access to sensitive threat-intelligence data, modify or delete information, alter configuration, or perform other privileged operations. The patch resolves the vulnerability by requiring authentication identifiers and passwords to be valid strings, rejecting empty passwords where they are not explicitly permitted, and assigning a randomly generated local password to LDAP-provisioned accounts instead of storing a hash derived from an empty password.