A URL validation flaw in the MISP dashboard button widget allowed a crafted relative-looking URL to be accepted as a local path while being interpreted by browsers as an external URL. The validation rejected URLs containing an explicit scheme, host, or user component, but did not reject paths beginning with a slash followed by a backslash, such as /\example.com. Some browsers normalize backslashes in URLs as forward slashes, which can turn this into a scheme-relative external navigation target. In addition, the generated href concatenated the reconstructed URL with the original URL, increasing the possibility of unsafe or malformed link generation. An attacker able to configure or influence a dashboard button URL could craft a button that appears to point inside the application but redirects users to an attacker-controlled site when clicked. This could be used for phishing, credential theft, or social engineering. The patch fixes the issue by rejecting empty paths and paths starting with /\, and by emitting only the reconstructed validated URL in the anchor href.

An authorization flaw existed in the MISP Event Template Importer overwrite workflow. When importing an event template in overwrite mode, the application checked whether a matching template already existed but did not verify that the importing user belonged to the organization that owned the existing template. As a result, an authenticated user with access to the template import functionality could forcibly overwrite an event template owned by another organization. Successful exploitation could allow unauthorized modification of another organization’s event template, potentially altering template structure, attributes, or metadata used for subsequent event creation or sharing workflows. Site administrators are not affected by this restriction, as they are explicitly allowed to overwrite templates across organizations. The issue was fixed by enforcing an ownership check before overwrite: non-site-admin users may only overwrite templates owned by their own organization.

A visibility control issue in the event template creation workflow allowed non-site-admin users to access private galaxies belonging to other organisations. The event template builder loaded all enabled galaxies without applying organisation or distribution-based access restrictions, potentially exposing private galaxy metadata such as galaxy type and description to users who should not have visibility. The issue has been fixed by restricting galaxy queries for non-site-admin users to galaxies owned by the user’s organisation or galaxies with a non-private distribution setting. Site administrators retain visibility of all enabled galaxies.

An authentication bypass vulnerability exists in MISP when LDAP mixed authentication is enabled with OTP enforcement. In deployments configured with LdapAuth.mixedAuth=true and Security.require_otp=true, users authenticated through an authentication plugin, such as LDAP, may have their authenticated session established during the application beforeFilter phase before the normal login flow enforces the OTP challenge. As a result, an attacker with valid primary authentication credentials could bypass the required OTP step by authenticating through the plugin-backed login flow and then directly accessing another application URL instead of completing the OTP verification page. This allows access to the application as the affected user without providing a valid TOTP, HOTP, or email OTP code. The issue affects configurations where plugin-based authentication is enabled and OTP is expected to be mandatory. The fix ensures that OTP requirements are checked immediately after plugin authentication and before the user session is established, redirecting users to the appropriate OTP challenge when required.

FlowIntel up to version 3.3.0 contains a server-side request forgery (SSRF) vulnerability in the external reference URL probe functionality in app/case/task.py. An attacker who can submit an external reference URL can cause the application server to issue an HTTP HEAD request to an attacker-specified destination. Due to insufficient validation of the URL scheme and resolved destination address, affected versions may allow requests to loopback, link-local, private, reserved, or other restricted network resources, potentially enabling interaction with internal services or cloud metadata endpoints from the server's network context.

A stored cross-site scripting (XSS) vulnerability exists in the notification panel of CTI Transmute in versions prior to the patched release. Notification messages containing user-controlled convert names were rendered in the notification bell dropdown using innerHTML without adequate sanitization. An attacker able to create or influence a convert name that is included in a notification could inject arbitrary JavaScript, which would execute in the browser of an authenticated user when they opened the notification panel. Successful exploitation could allow the attacker to perform actions in the victim's session or access information available to the application in the browser context. The issue was remediated by constructing notification elements through DOM methods and assigning notification message content via textContent instead of innerHTML. This vulnerability was only present on a development branch.

The CSP report endpoint in MISP intended to limit logged CSP reports to 1 KB but incorrectly allowed reports up to 1 MB before truncation. On deployments where the endpoint is reachable by untrusted clients, this could allow attackers to generate excessive log volume and contribute to resource exhaustion or log flooding.

A vulnerability was identified in the ShadowAttribute proposal creation workflow. The add action accepted user-controlled ShadowAttribute request data without removing the id field before saving the record. Because the underlying framework treats a supplied primary key as an instruction to update an existing record, an authenticated user able to submit shadow attribute proposals could provide the identifier of an existing ShadowAttribute and cause that record to be updated instead of creating a new proposal. This can result in unauthorized modification of existing shadow attributes, potentially affecting proposals associated with events the user should not be able to alter. Depending on deployment configuration and accessible API responses, the issue may also expose or move proposal data across event contexts. The vulnerability is caused by trusting a client-supplied primary key during object creation. The fix removes the id field from incoming ShadowAttribute data before processing, ensuring that the endpoint always creates a new proposal rather than updating an existing one. This has been fixed in MISP 2.5.38.

MISP’s OIDC authentication plugin allowed automatic linking of an OIDC identity to an existing local user account based on the email claim when the local account had no stored sub value. Under insecure or untrusted IdP configurations where email ownership is not enforced, an attacker with a valid OIDC token could assert a victim’s email address and authenticate as that user, leading to account takeover.

Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in misp allows Stored XSS. This issue affects MISP before 2.5.37. A stored cross-site scripting vulnerability exists in the template element attribute handling logic. The application accepted arbitrary values for the TemplateElementAttribute type and category fields without validating them against the known MISP attribute type and category definitions. An attacker with permission to create or modify template element attributes could store a crafted type value. This affects the old templating (not more accessible in 2.5.37) engine from MISP which will be removed in 2.5.38