CVE-2026-85957 in MarkLogic Server
Summary
by MITRE • 10/12/2026
Affected Progress MarkLogic Server 11.x releases before 11.3.7 use a SAML parser configuration that can process external DTDs or entities, which could result in unintended network access or information disclosure.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 10/12/2026
The vulnerability identified in Progress MarkLogic Server versions prior to 11.3.7 stems from an insecure configuration within the Security Assertion Markup Language (SAML) parser component. SAML is a standard protocol used for exchanging authentication and authorization data between parties, specifically between an identity provider and a service provider. In this specific implementation, the underlying XML processing engine was configured in a manner that permits the parsing of external Document Type Definitions (DTDs) and external entities. This configuration deviation from secure defaults creates a significant attack surface because it allows attackers to manipulate how the server processes incoming SAML assertions or related XML data structures. The core technical flaw lies in the absence of strict restrictions on entity resolution, which is a common requirement for securing XML parsers against abuse.
From a technical perspective, allowing external DTDs and entities enables several classes of attacks that are well-documented in cybersecurity literature. Most notably, this configuration makes the system susceptible to Server-Side Request Forgery (SSRF) attacks via XXE injection techniques. An attacker can craft malicious SAML requests containing references to internal or external resources. When the server processes these requests, it may attempt to fetch data from those referenced locations. This behavior can lead to unintended network access where the server acts as a proxy for an attacker, potentially scanning internal networks, accessing cloud metadata services such as AWS EC2 instance metadata, or reaching other sensitive backend systems that are not directly exposed to the public internet but are accessible via the application server's network interface.
Furthermore, this vulnerability facilitates information disclosure through XML External Entity (XXE) attacks. By defining entities that read local files on the server operating system, an attacker can cause the contents of those files to be included in the parsed output or error messages returned by the SAML endpoint. This could result in the exposure of sensitive configuration files, source code, database credentials, or other proprietary data stored within the MarkLogic Server environment. The impact is compounded if the server runs with elevated privileges, as it may allow reading system-level files that would otherwise be inaccessible to standard application users.
The operational impact of this vulnerability extends beyond immediate data theft. It can serve as a foothold for further exploitation within the network infrastructure. If an attacker successfully leverages SSRF capabilities, they might pivot through trusted connections to compromise other services running on internal hosts. This undermines the principle of least privilege and compromises the integrity of the entire security architecture surrounding the MarkLogic deployment. Additionally, in some configurations, XXE vulnerabilities can lead to denial-of-service conditions by causing the server to consume excessive CPU or memory resources while resolving complex entity chains, thereby affecting availability for legitimate users.
To mitigate this risk, organizations running affected versions must upgrade immediately to Progress MarkLogic Server version 11.3.7 or later, where these parsing restrictions have been enforced. Until an upgrade is feasible, administrators should implement network-level controls such as firewall rules that restrict the server's outbound internet access and prevent it from reaching internal metadata endpoints like 169.254.169.254 commonly used in cloud environments. Input validation at a reverse proxy or web application firewall layer can also help by blocking XML payloads containing suspicious entity declarations before they reach the MarkLogic parser. It is critical to treat this as a high-severity issue due to its potential for remote code execution implications through SSRF and significant data exfiltration risks.
This vulnerability aligns with CWE-611, which describes Improper Restriction of XML External Entity Reference, and CWE-918, Server-Side Request Forgery (SSRF). In the context of the MITRE ATT&CK framework, this flaw relates to techniques involving Taint Source: Untrusted Data in Web Applications and potentially Tainted Input Processing. The exploitation path typically involves Initial Access through a vulnerable web service component followed by Discovery or Collection phases if SSRF is leveraged to probe internal networks. Security teams should prioritize patching this specific component as part of their routine vulnerability management lifecycle, ensuring that all XML-based authentication protocols are hardened against entity injection attacks in accordance with OWASP guidelines for secure coding practices.