# CVE-2026-91399: Oracle Primavera P6 Enterprise unauthorized data modification in Web Access

Source: https://junglewise.ai/threats/cve-2026-91399-vulnerability-in-the-primavera-p6-enterprise-project-portfolio  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-20. Updated: 2026-10-20  
License: CC BY 4.0 with a link back

CVE-2026-91399 · Severity: medium · CVSS 4.3 · Published 2026-10-20

Oracle Primavera P6 Enterprise is a project portfolio management system used by construction and engineering organizations to manage large-scale projects and budgets. A vulnerability in its web interface allows authenticated users with low privileges to modify, insert, or delete project data they should not have access to, compromising project integrity and potentially causing financial or scheduling impacts.

Technologies: [Oracle Primavera P6 Enterprise Project Portfolio Management](https://junglewise.ai/threats/technologies/primavera-p6-enterprise-project-portfolio-management). Vendors: [Oracle](https://junglewise.ai/threats/vendors/oracle).

## Quick answers

**Is CVE-2026-91399 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-91399 being exploited in the wild.

**How severe is CVE-2026-91399?** Medium severity, with a CVSS score of 4.3, published 20 October 2026.

**Which products and versions are affected?** Oracle Primavera P6 Enterprise Project Portfolio Management 21.12.0.0-21.12.21.9, 22.12.0.0-22.12.21.4, 23.12.0-23.12.20, 24.12.0-24.12.16, 25.12.0-25.12.8.

**Is there a fix for CVE-2026-91399?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-91399 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-91399?** Check whether you run Oracle Primavera P6 Enterprise Project Portfolio Management at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is an authorization flaw in the Web Access component that allows low-privileged authenticated users to perform unauthorized data modification operations via HTTP requests. The attack requires network access and valid credentials but no user interaction. Affected versions span from 21.12.0.0 through 25.12.8 across multiple release branches.

## Affected products

- Oracle Primavera P6 Enterprise Project Portfolio Management 21.12.0.0-21.12.21.9, 22.12.0.0-22.12.21.4, 23.12.0-23.12.20, 24.12.0-24.12.16, 25.12.0-25.12.8

## Timeline

- 2026-10-20: disclosed

## References

- [https://www.oracle.com/security-alerts/cpuoct2026.html](https://www.oracle.com/security-alerts/cpuoct2026.html)

## Related threats

- [Oracle Primavera P6 Enterprise Project Portfolio Management CSRF in Web Access](https://junglewise.ai/threats/cve-2026-91376-vulnerability-in-the-primavera-p6-enterprise-project-portfolio)
- [Oracle Primavera P6 EPPM unauthenticated compromise in Web Access](https://junglewise.ai/threats/cve-2017-3324-oracle-primavera-p6-eppm-unauthenticated-compromise-in-web-access)
- [Oracle Primavera P6 EPPM improper access control in Team Member](https://junglewise.ai/threats/cve-2017-3263-oracle-primavera-p6-eppm-improper-access-control-in-team-member)