MPXJ Security Update Addresses 2 Vulnerabilities
Tech GuruQuick Answer
MPXJ has two distinct file-reader fixes in this notice: CVE-2026-61570 affects Merlin project parsing and is fixed in 16.4.1; CVE-2026-65829 affects Primavera P3 PRX and SureTrak STX extraction and is fixed in 16.5.0. Version 16.4.1 alone does not resolve both. Inventory the actual library and wrapper used by import jobs, then select a supported release that includes these and any later applicable fixes.
Confirm Scope And Apply The Supported Fix
What to do now: identify services that import Merlin, PRX or STX files, including embedded MPXJ dependencies. Until upgraded, stop accepting those formats from untrusted sources. Confirm the wrapper/package migration path before rebuilding and redeploying each consumer.
Source recheck: October 2, 2026 UTC. The linked project advisories were checked for this revision; deployment applicability and successful remediation still require local evidence. Recheck the supported release before changing production.
Scope And Authority
| Product scope | MPXJ MerlinReader and Primavera P3 PRX/SureTrak STX readers; Maven, Python, Ruby and the listed NuGet wrappers |
|---|---|
| Advisory | GHSA-5vvx-3h34-f3gj / GHSA-7952-gx68-cjqr |
| CVEs | CVE-2026-61570, CVE-2026-65829 |
| Authoritative release date | 2026-07-03 UTC (project advisory dates, not database ingestion) |
| Authority revision date | 2026-07-10, 2026-07-23 UTC (project advisory dates, not database ingestion) |
| Affected versions | Merlin XXE: 5.5.5 up to, but excluding, 16.4.1. PRX/STX traversal: 7.3.0 up to, but excluding, 16.5.0. Apply the range to the exact package/ecosystem listed in each advisory, including transitive copies. |
| Fixed version | Merlin XXE: 16.4.1. PRX/STX traversal: 16.5.0. Maven: net.sf.mpxj:mpxj; Python/Ruby: mpxj; .NET: check MPXJ.Net migration for legacy net.sf.mpxj, net.sf.mpxj-for-csharp and net.sf.mpxj-for-vb consumers. These are issue-specific minimum fixes, not a claim that an old minimum release covers later advisories. |
| CVSS base score | 5.3 / 7.5 (CVSS v3) |
| CVSS severity | Medium to High |
| Exploitation status | Not stated by the authority; no exploitation claim is inferred. |
What Changed
MerlinReader allowed XML document-type declarations in project database content, enabling file reads. The author notes that subsequent parsing makes exfiltration of that data unlikely; the finding does not establish confirmed data theft. The separate PRX/STX issue can write extracted files outside their intended directory. Rejecting untrusted input is temporary containment, not evidence that the library is patched.
What To Validate Now
- Inventory. Record the MPXJ library and wrapper versions inside each importer, the accepted formats and the source of submitted project files.
- Establish applicability. Compare each accepted format with its separate affected range above. Disabling Merlin input does not address PRX/STX extraction.
- Remediate. Upgrade through the official package channel to a supported release covering both applicable issues and later advisories; rebuild consumers and verify that no older transitive library remains.
- Validate. In an isolated test environment, confirm normal imports for the formats you use and the intended filesystem/network boundaries. Record the loaded library version, not only a changed dependency manifest.
- Retain evidence. Preserve asset and owner identifiers, the applicability decision, before-and-after versions, change approval, installation output, validation results, and any exception or rollback record.
Operational Cautions
Use the exact supported release stream and repository. Test dependencies, clusters, integrations, and rollback before broad deployment; a CVSS rating or reachable feature is not evidence of exploitation.
Evidence To Retain
- Exact product, release stream, package or application version, enabled feature, environment, and accountable owner.
- UTC timestamps, authority revision, approved change record, installer or package-manager output, and resulting version.
- Relevant logs and monitoring evidence, test results, exceptions, compensating controls, and rollback decisions.
Related TechGeeks Resources
Authoritative References
Correction policy: If the authority changes affected versions, fixed versions, severity, exploitation information, mitigations, or required action, TechGeeks will update this notice and its verification date.
