The html_to_markdown expansion module in MISP Modules contains a server-side request forgery (SSRF) vulnerability in its is_safe_url() URL validation function. The BLOCKED_RANGES list used to reject unsafe destination addresses was incomplete, omitting several critical IP address ranges. Specifically, the following ranges were not blocked: 0.0.0.0/8 (unspecified, which routes to loopback on Linux), 100.64.0.0/10 (carrier-grade NAT per RFC 6598), ::/128 (IPv6 unspecified), fc00::/7 (IPv6 Unique Local Addresses), and fe80::/10 (IPv6 link-local). The existing list only covered IPv4 loopback (127.0.0.0/8), RFC 1918 private ranges, IPv4 link-local (169.254.0.0/16), and IPv6 loopback (::1/128).
An authenticated user with the ability to create or modify MISP attributes that trigger the html_to_markdown expansion module could supply URLs pointing to these unblocked internal address ranges. Because the module fetches the URL server-side to convert HTML content to Markdown, the request is made from the MISP server's network context. This allows an attacker to probe and read responses from internal services, carrier-grade NAT infrastructure, or link-local endpoints that would otherwise be unreachable from external networks. IPv4-mapped IPv6 forms (e.g., [::ffff:0.0.0.0]) also bypassed the existing checks.
The security impact is primarily confidentiality: an attacker can read data served by internal services reachable from the MISP server. The MISP instance itself is not compromised, but it is abused as a proxy to access otherwise restricted network resources.
CVE-2026-106512 is a high-severity vulnerability in the MISP sachertortephp component where the CakeResponse::download() method improperly sanitizes filenames used in the Content-Disposition HTTP header. This flaw allows an authenticated user to craft filenames that inject HTTP header content, leading to stored cross-site scripting (XSS) when other users view affected pages. The vulnerability arises from two injection vectors: control characters causing header omission and double-quote characters enabling header parameter injection. Exploitation can result in session hijacking, data exfiltration, and unauthorized actions within the application context.
The cisco_firesight_manager_ACL_rule_export module in misp-modules generates a shell script (.sh) that authenticates to and calls the Cisco fireSIGHT Manager API. The module interpolates configuration values (IP address, login, password, domain ID, policy ID) and MISP attribute values (destination IPs, URLs, event info comments) directly into single-quoted shell string assignments without any escaping or sanitization. Because the values are placed inside single-quoted shell strings, any value containing a single-quote character (e.g., a crafted ip-dst or url attribute value submitted to MISP) breaks out of the quoting context, allowing an attacker to inject arbitrary shell commands into the exported script. A security analyst who subsequently executes the generated .sh file unmodified would run the injected commands with their own privileges, potentially exposing fireSIGHT Manager credentials, modifying ACL rules, or compromising the analyst workstation. Additionally, the module contained a secondary defect where the variable 'config' was only assigned inside a conditional block but referenced unconditionally afterward, causing a NameError (denial of service) when the request payload lacked a 'config' key. The vulnerability requires the attacker to have the ability to submit MISP events or attributes containing a single-quote character and the victim to execute the exported script. No authentication bypass is required beyond standard MISP event-submission privileges.
In the MISP sachertortephp library, the Xml::build() static method in lib/Cake/Utility/Xml.php contains a logic error in the conditional that gates network-based XML fetching. The original condition was written as: $options['readFile'] && strpos($input, 'http://') === 0 || strpos($input, 'https://') === 0. Because PHP's && operator has higher precedence than ||, the expression is evaluated as ($options['readFile'] && strpos($input, 'http://') === 0) || strpos($input, 'https://') === 0. As a result, when a caller explicitly sets the readFile option to false to disable file and URL reading, an input string beginning with https:// still satisfies the condition and triggers a network fetch via HttpSocket (configured to follow up to 10 redirects). The http:// branch is correctly gated by the readFile flag, but the https:// branch is not. An attacker who can influence the $input parameter passed to Xml::build() can therefore force the application to issue an outbound HTTPS request to an attacker-controlled or internal URL, even though the caller intended to suppress all remote reads. The fetched response is parsed as XML and may be returned to the caller, enabling information disclosure from internal services or external targets. This constitutes a Server-Side Request Forgery (SSRF) weakness with an information-disclosure impact. The vulnerability requires that the code path in Xml::build() be reachable with attacker-controlled input and that the readFile option be set to false (or the caller expects it to be false).
CVE-2026-77761 is a parser state isolation vulnerability in the misp-stix component of MISP. It causes data from a previously processed STIX document to be retained and mixed into subsequent MISP events when the same parser instance is reused. This affects STIX 1 and STIX 2 parsers, leading to incorrect associations and potential limited information disclosure between events. The vulnerability requires reuse of parser instances and specific document ordering, increasing exploitation complexity. There is no impact on availability or code execution.
CVE-2026-77755 is a denial-of-service vulnerability in misp-stix affecting versions up to and including 2026.7.8. It arises from improper handling of STIX 1 and STIX 2 documents during import, where sys.exit() calls cause process termination and no input size limits allow excessive memory and CPU consumption. Exploitation can terminate the importer process or degrade service availability.
CVE-2026-77751 is a path traversal vulnerability in misp-stix affecting the handling of MISP object template names during STIX 2 import and export. The vulnerability allows crafted object names containing path traversal sequences to escape the intended template directory and load arbitrary definition.json files accessible to the process. This can lead to unintended disclosure of local data and modification of object metadata. The issue is mitigated by patches that enforce strict validation of object-template names, restricting them to safe characters and replacing invalid names with a generic placeholder.
CVE-2026-77710 is a medium severity vulnerability in the misp-stix component of MISP that allows crafted STIX documents to manipulate security-sensitive attribute metadata during import. The vulnerability arises because the parser selection for STIX documents is based on untrusted metadata controlled by the document producer, enabling attackers to spoof MISP-origin indicators. This leads to improper input validation where attacker-supplied STIX bundles can inject unauthorized attribute properties such as distribution, sharing restrictions, and tags. This can cause information to be shared against organizational policies or influence downstream processing. The issue is addressed by introducing an explicit classification parameter and restricting accepted attribute fields via an allow-list.
Affected versions of MISP cti-transmute expose several state-changing account operations as GET requests:
*
/account/follow
*
/account/delete_notification
*
/account/mark_notification_read
*
/account/mark_all_read
These endpoints require authentication, but before the fix they could be invoked with simple GET requests. That makes them susceptible to cross-site request forgery because a third-party site can induce the victim’s browser to send authenticated GET requests automatically.
The patch converts the actions to POST or DELETE and updates the frontend to include an X-CSRFToken header, providing explicit CSRF protection for those state-changing operations.
Affected versions of cti-transmute improperly handle conversion-table values passed through the search highlighting feature. The highlight() function previously returned the underlying text directly when no search query was supplied, or performed a regex replacement that inserted <mark> tags without first escaping the original content. Because the resulting value is used by an HTML-rendering sink, malicious markup contained in conversion data could be interpreted as HTML rather than displayed as text.
The fix introduces a shared highlightMatches() helper that first converts special characters such as <, >, &, and quotes into HTML entities. Only after escaping does the code insert the application-controlled <mark> element used for search highlighting.
Affected versions of cti-transmute contain an SSRF vulnerability in the /fetch_misp_event and /misp_search_events endpoints.
The URL validation routine checked whether a supplied hostname was itself an IP literal and rejected private, loopback, link-local, or reserved IPs. However, ordinary domain names were accepted without resolving them first. An attacker could therefore use a hostname whose DNS record pointed to an internal address and cause the cti-transmute server to issue requests into its internal network. The commit explicitly states that anonymous callers could make the server request the internal target and read the response.
The fix resolves hostnames using socket.getaddrinfo(), checks that every resolved address is globally routable, and additionally places @login_required on both affected MISP fetch/search routes.
Affected versions of cti-transmute allow a tag's icon value to be stored and later interpolated into HTML through Vue's v-html. The helper mapIcon() previously constructed an HTML string directly from the icon value:
<i class="fas fa-${name}"></i>
Because the icon is user-supplied, a crafted value could break out of the intended markup and inject attacker-controlled HTML. When the affected tag was later rendered, including on the administrative triage interface, the payload could execute in the viewer's browser.
The patch mitigates the issue at multiple layers: v-html is replaced with Vue :class binding, mapIcon() now returns only a constrained FontAwesome class string, and the backend validates icons against the FontAwesome catalogue or a strict [a-z0-9-]{1,40} slug pattern before storing them.
Affected versions of cti-transmute insufficiently validate saved graph configuration data. Graph configurations can contain style properties that are later consumed by Pivotick, and Pivotick interprets svgIcon as HTML. Because saved configurations may be created by one user and later displayed to other users—including administrators—a malicious user could store a crafted svgIcon value that executes script in another viewer’s browser.
The fix introduces a strict configuration schema on both the server and client. Only known properties are accepted, style entries are limited to shape, color, and size, and dangerous properties such as svgIcon and iconClass are explicitly rejected. Existing stored configurations are also sanitized when listed and again before being applied in the browser.
Affected versions of cti-transmute render data obtained from a remote MISP instance into the event-browser interface using HTML interpolation. Because fields such as event IDs, event information, organization names, tags, tag colors, TLP labels, distribution labels, and error/flash text may be controlled by the remote MISP server, a malicious or compromised remote instance could return crafted values that inject HTML or script-capable content into the cti-transmute interface.
The patch explicitly notes that remote-derived values must not reach innerHTML, and replaces string-built rows and badges with DOM nodes populated through textContent. It also restricts remote-controlled tag colors to six-digit hexadecimal values, preventing malicious CSS values such as url(...).
Affected versions of cti-transmute fail to HTML-escape attacker-controlled values used in ECharts Sunburst and Treemap tooltip formatters. Slice names may originate directly from STIX or MISP data, including STIX types, relationship_type, pattern prefixes, and MISP category/type values. Since ECharts interprets the formatter return value as HTML, crafted values can inject markup or script-capable content into the tooltip.
An attacker who can cause malicious conversion data to be processed can therefore inject content that executes when another user views the visualization and hovers over the affected slice. The patch replaces direct interpolation with dedicated formatter functions that call escapeHtml() on p.name, p.data.value, and p.value.
Affected versions of cti-transmute allow authenticated users to add or remove emoji reactions on comments without first checking whether those users are authorized to view the target comment.
The vulnerable react() handler passed an attacker-controlled comment_id directly to comments_repo.toggle_reaction() after only validating that the ID existed syntactically and that the requested emoji was permitted. Because comment-level visibility was not enforced, a user who could identify the ID of a private or otherwise inaccessible comment could modify reaction state on that comment despite lacking permission to access it.
The fix retrieves the target comment, rejects missing or deleted comments, retrieves its associated conversion, and enforces access.can_see_comment(current_user, comment, conversion). Unauthorized requests now receive HTTP 403.
Affected versions of cti-transmute fail to apply comment-level access-control rules when generating evaluation report exports. Although normal comment retrieval filters comments according to conversion visibility, comment privacy, ownership, authorship, and administrative privileges, build_evaluation_report() previously included all evaluation comments without applying those rules.
Consequently, a user who was authorized to view a conversion could export its evaluation report as Markdown or PDF and obtain private evaluation comments that should only have been visible to the conversion owner, the comment author, or an administrator. The leaked report data also contained the comment author's name. The fix passes the requesting user into the report builder and filters every evaluation comment using the shared access.can_see_comment() authorization function.
Affected versions of MISP cti-transmute disclose users' email addresses through the account following-list endpoint. When an authenticated user follows another account, get_following() includes the followed user's email field in the API response alongside their name, user ID, and follow date. Because the email address is not required for the functionality and other related user lists omit it, an authenticated attacker could systematically follow users and collect their email addresses. The fix removes user.email from the returned object.
In affected versions of MISP cti-transmute, the conversion-history details endpoint performs an incomplete authorization check. When a history record references a deleted conversion, the associated conversion lookup returns None. The previous logic only denied access when the conversion object existed and the visibility check failed. As a result, deleted conversions bypassed the authorization check and their retained history input/output could be disclosed to a user able to request the corresponding history entry. The July 22, 2026 commit changes the logic to deny access whenever the conversion is missing or the requester lacks permission
CTI-Transmute is affected by a stored cross-site scripting (XSS) vulnerability in the conversion graph used to visualise converted MISP and STIX content.
Attacker-controlled values originating from converted CTI data were passed to multiple HTML-parsing sinks in the graph user interface without sufficient neutralisation. In particular, node labels, node sublabels, edge labels, node properties, edge properties, and node types could contain crafted HTML or JavaScript content.
The Pivotick graph library renders some of these values through HTML-parsing operations. Consequently, a malicious value such as an HTML element containing an event handler could be interpreted as markup rather than displayed as plain text. The first remediation explicitly notes that Pivotick rendered node and edge labels as HTML and therefore introduced escaping before data was handed to the graph renderer.
A separate vulnerable sink was present in the Open raw JSON functionality. The raw object associated with a graph node was inserted into a new document using document.write() and an interpolated HTML string. Crafted JSON content could therefore break out of the intended <pre> element and inject executable markup. The fix replaced this construction with DOM APIs and assigns the JSON using textContent.
The initial correction did not cover all Pivotick rendering paths. A subsequent patch addressed additional XSS vectors in the graph properties panel. Values derived from the original CTI object—including property names, property values, hash algorithm names, child attributes, edge properties, and STIX object types—could still reach Pivotick's HTML resolver. According to the patch, Pivotick's tryResolveHTMLElement processes string values using template.innerHTML, allowing malicious markup to execute when a graph node is hovered over or selected.
The complete remediation therefore:
* HTML-escapes node labels, node sublabels, and edge labels before they are passed to Pivotick.
* Restricts graph node type values to a safe identifier character set.
* Wraps node and edge property values in DOM elements populated through textContent, preventing Pivotick from treating attacker-controlled strings as HTML.
* Replaces the raw-JSON popup's interpolated document.write() with DOM construction and textContent.