CVE-2026-65829 is a medium-severity (CVSS 5.3) Path Traversal vulnerability in net.sf.mpxj:mpxj. A fix is available for net.sf.mpxj:mpxj — see the affected versions and patch details below.
MPXJ: Potential Path Traversal Vulnerability in Primavera P3 PRX and SureTrak STX readers
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-65829.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2026-65829 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 394,803 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
net.sf.mpxj:mpxj.NETMPXJ.Net.NETnet.sf.mpxj.NETnet.sf.mpxj-for-csharp.NETnet.sf.mpxj-for-vb🐍mpxj💎mpxjReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven, NuGet packages — download data is not available via public APIs for these ecosystems.
Description
MPXJ is an open source library to read and write project plans from a variety of file formats and databases. From 7.3.0 until 16.5.0, reading a suitably crafted Primavera P3 PRX or SureTrak STX file can cause MPXJ to write files to arbitrary locations in the filesystem. This issue is fixed in version 16.5.0.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | net.sf.mpxj:mpxj | ≥ 7.3.0&&< 16.5.0 | 16.5.0net.sf.mpxj:mpxj:16.5.0 |
| .NETNuGet | MPXJ.Net | ≥ 7.3.0&&< 16.5.0 | 16.5.0dotnet add package MPXJ.Net --version 16.5.0 |
| .NETNuGet | net.sf.mpxj | ≥ 7.3.0&&< 16.5.0 | 16.5.0dotnet add package net.sf.mpxj --version 16.5.0 |
| .NETNuGet | net.sf.mpxj-for-csharp | ≥ 7.3.0&&< 16.5.0 | 16.5.0dotnet add package net.sf.mpxj-for-csharp --version 16.5.0 |
| .NETNuGet | net.sf.mpxj-for-vb | ≥ 7.3.0&&< 16.5.0 | 16.5.0dotnet add package net.sf.mpxj-for-vb --version 16.5.0 |
| 🐍PyPI | mpxj | ≥ 7.3.0&&< 16.5.0 | 16.5.0pip install --upgrade 'mpxj==16.5.0' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for net.sf.mpxj:mpxj, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update net.sf.mpxj:mpxj to 16.5.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-65829 is resolved across your whole dependency graph.
Workarounds
Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.
Frequently Asked Questions
Is CVE-2026-65829 in your dependencies?
Find it across Maven, NuGet, PyPI, including transitive dependencies.