CVE-2026-71375 Overview
CVE-2026-71375 is an XML External Entity (XXE) vulnerability in Hitachi Cosminexus Component Container. The flaw stems from improper restriction of XML external entity references [CWE-611] within the application server component. An attacker can craft malicious XML input to force the parser to resolve external entities, leading to information disclosure and denial of service conditions on affected systems.
The vulnerability affects a broad range of Cosminexus Component Container versions from the 09-00 branch through 11-70 releases. Hitachi documented the issue in security advisory HITACHI-SEC-2026-131.
Critical Impact
Remote attackers can exploit this XXE flaw over the network without authentication to disclose sensitive server-side data or disrupt service availability.
Affected Products
- Hitachi Cosminexus Component Container 11-70-01 before 11-70-03, 11-60 before 11-60-03, 11-50 through 11-50-03, 11-40 through 11-40-03
- Hitachi Cosminexus Component Container 11-30 through 11-30-08, 11-20 before 11-20-10, 11-10 through 11-10-11, 11-00 before 11-00-13
- Hitachi Cosminexus Component Container 09-87 before 09-87-10, 09-80 before 09-80-05, 09-70 before 09-70-28, 09-50 through 09-50-22, and 09-00 through 09-00-18
Discovery Timeline
- 2026-09-08 - CVE-2026-71375 published to the National Vulnerability Database
- 2026-09-08 - Last updated in NVD database
Technical Details for CVE-2026-71375
Vulnerability Analysis
Cosminexus Component Container is a Java EE application server used to host enterprise applications. The vulnerability resides in an XML parsing routine that fails to disable external entity resolution. When the parser processes attacker-controlled XML, it fetches referenced external entities from local files or remote URIs.
An attacker can use this behavior to read files accessible to the application server process. The same primitive can trigger denial of service through entity expansion or by referencing slow or unresponsive external resources. The attack requires no privileges and no user interaction, though exploitation complexity is elevated due to specific parser conditions that must be met.
Root Cause
The defect maps to CWE-611: Improper Restriction of XML External Entity Reference. The XML parser used by the affected component accepts external entity declarations in DOCTYPE definitions without applying secure processing features. Secure defaults such as disabling DOCTYPE, disabling external general entities, and disabling external parameter entities are not enforced.
Attack Vector
Exploitation occurs over the network by submitting crafted XML payloads to endpoints handled by the vulnerable container. A typical XXE payload defines an external entity that references a local file URI such as file:///etc/passwd or a remote HTTP resource, then references that entity within the XML body. When the parser resolves the entity, its contents are either reflected in a response, exfiltrated out-of-band, or trigger resource exhaustion. Refer to the Hitachi Security Advisory HITACHI-SEC-2026-131 for vendor-specific technical details.
Detection Methods for CVE-2026-71375
Indicators of Compromise
- Inbound HTTP requests containing XML payloads with <!DOCTYPE and <!ENTITY declarations, particularly those referencing SYSTEM identifiers
- Outbound network connections from the Cosminexus Component Container process to unexpected external hosts, indicating out-of-band XXE exfiltration
- Application server logs showing XML parser errors related to entity resolution or unexpected file access from the JVM process
Detection Strategies
- Inspect HTTP request bodies at the web application firewall or reverse proxy for XML content containing external entity declarations
- Correlate application server process activity with unexpected file reads outside the standard application directory tree
- Monitor DNS queries originating from the application server for suspicious lookups that could indicate out-of-band data exfiltration channels
Monitoring Recommendations
- Enable verbose logging on the XML processing subsystem of Cosminexus Component Container to capture parser warnings and DOCTYPE processing events
- Baseline normal outbound network flows from the application server tier and alert on deviations
- Track access to sensitive filesystem paths by the container's runtime user account
How to Mitigate CVE-2026-71375
Immediate Actions Required
- Identify all Cosminexus Component Container deployments and inventory their installed version strings against the affected ranges
- Apply the vendor-supplied fixed release for the corresponding version branch as documented in HITACHI-SEC-2026-131
- Restrict network exposure of the application server to trusted client segments until patching is complete
Patch Information
Hitachi has released fixed versions across each supported branch. Upgrade to 11-70-03, 11-60-03, 11-20-10, 11-00-13, 09-87-10, 09-80-05, or 09-70-28 or later, depending on the deployed branch. Consult the Hitachi Security Advisory HITACHI-SEC-2026-131 for the complete mapping of fixed releases and installation guidance.
Workarounds
- Deploy a web application firewall rule to block or strip XML payloads containing <!DOCTYPE or <!ENTITY declarations on endpoints that do not require them
- Where custom application code invokes XML parsers directly, disable DOCTYPE processing and external entity resolution at the parser level
- Limit the file system and network egress permissions of the JVM user account running the application server to reduce the blast radius of a successful XXE
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.