CVE-2026-94401 in MISP
Summary
by MITRE • 09/21/2026
MISP has a file-handling vulnerability that could let certain authenticated users make the server read files or access internal network services.
When importing an XML file, MISP did not properly verify that the uploaded content was actually XML. Because of this, a user with permission to modify data could upload a file containing a local file path or a web address instead.
If a local file path was supplied, MISP could read that file from the server. If a URL was supplied, MISP could make a request to that address, including systems that may only be reachable from inside the organization’s network.
The vulnerability could therefore expose sensitive local files and allow unauthorized requests to internal services.
Exploitation required a valid MISP account with modify permissions, but no additional user interaction was needed.
Version affected: <2.5.47
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Analysis
by VulDB Data Team • 09/21/2026
MISP versions prior to 2.5.47 contain a critical file-handling vulnerability that allows authenticated users with data modification privileges to perform unauthorized server-side requests and read sensitive local files from the host system. This flaw stems from an insufficient validation mechanism during the XML import process, where the application fails to rigorously verify that the uploaded content is strictly valid XML before processing it. Instead of rejecting malformed or non-XML payloads, the parser proceeds with execution on data provided by the user, creating a pathway for malicious input to be interpreted as executable instructions rather than passive data structures. This lack of strict type checking and schema validation represents a fundamental failure in input sanitization, allowing attackers to inject arbitrary file paths or Uniform Resource Locators into fields that are subsequently processed by underlying libraries responsible for parsing XML documents.
The technical exploitation of this vulnerability relies on the behavior of standard XML parsers which support external entity resolution. By uploading a crafted payload containing a Local File Inclusion directive, an attacker can force the MISP server to read arbitrary files from its own filesystem. This capability effectively bypasses access controls that would normally restrict file reads to specific directories or user-owned resources, potentially exposing configuration files, database credentials, source code, or other sensitive data stored on the server disk. Furthermore, if the payload contains a Uniform Resource Locator pointing to an internal network address, the MISP instance acts as a blind server-side request forgery vector. The application initiates HTTP requests to targets that may be inaccessible from external networks due to firewall rules or network segmentation, thereby enabling reconnaissance of internal infrastructure and potential exploitation of other services running on those internal hosts based solely on their response codes or error messages.
From an operational impact perspective, this vulnerability significantly compromises the confidentiality and integrity of the MISP deployment as well as the broader organizational network. The ability to read local files can lead to credential theft if configuration files containing database passwords or API keys are accessed. Additionally, the capacity to make requests to internal services transforms a single compromised application account into a pivot point for lateral movement within the organization’s intranet. Attackers with modify permissions do not require any additional user interaction beyond uploading the malicious file through the standard import interface, making this vulnerability highly exploitable in environments where users are trusted but accounts may be shared or poorly secured. The impact extends beyond data exposure to include potential denial of service if internal services are overwhelmed by repeated requests generated via the vulnerable application.
This flaw is categorized under CWE-94 Improper Control of Generation of Code (Code Injection) and specifically relates to CWE-611 Improper Restriction of XML External Entity Reference when considering the mechanism used for file inclusion, as well as CWE-200 Exposure of Sensitive Information to an Unauthorized Actor. In terms of adversary tactics, this vulnerability aligns with ATT&CK technique T1552 Unsecured Credentials if local files containing secrets are accessed, and T1071 Application Layer Protocol if the internal network requests are used for further communication or data exfiltration channels. It also reflects aspects of T1046 Network Service Discovery when probing internal services through blind SSRF responses.
To mitigate this vulnerability, organizations running MISP versions earlier than 2.5.47 must immediately upgrade to version 2.5.47 or later where the issue has been resolved by implementing stricter input validation and disabling external entity processing in XML parsers. Administrators should also enforce principle of least privilege for user accounts within MISP, ensuring that only necessary personnel have data modification permissions. Network-level controls such as web application firewalls can provide an additional layer of defense by inspecting incoming requests for patterns indicative of XXE or SSRF attacks, although upgrading the software remains the primary and most effective remediation strategy. Regular security audits and penetration testing should be conducted to verify that input validation mechanisms are robust against evolving attack vectors targeting XML processing components in web applications.