# CVE-2026-91435: Oracle Siebel CRM Deployment denial of service in Server Infrastructure

Source: https://junglewise.ai/threats/cve-2026-91435-vulnerability-in-the-siebel-crm-deployment-product-of-oracle  
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-2026-91435 · Severity: medium · CVSS 6.5 · Published 2026-10-20

Oracle Siebel CRM Deployment is a customer relationship management system that manages business operations and customer interactions. A low-privileged attacker with network access can exploit this vulnerability to crash or hang the system, causing complete unavailability and service outages.

Technologies: [Oracle Siebel CRM Deployment](https://junglewise.ai/threats/technologies/siebel-crm-deployment). Vendors: [Oracle](https://junglewise.ai/threats/vendors/oracle).

## Quick answers

**Is CVE-2026-91435 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-91435 being exploited in the wild.

**How severe is CVE-2026-91435?** Medium severity, with a CVSS score of 6.5, published 20 October 2026.

**Which products and versions are affected?** Oracle Siebel CRM Deployment 17.0-26.9.

**Is there a fix for CVE-2026-91435?** 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-2026-91435 attacked?** It is attacked over the network, in a hosted service.

**Am I affected by CVE-2026-91435?** Check whether you run Oracle Siebel CRM Deployment 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

A denial-of-service vulnerability exists in the Server Infrastructure component of Siebel CRM Deployment, exploitable via HTTP by a low-privileged authenticated attacker with network access. Successful exploitation causes a hang or repeated crash of the application, resulting in complete availability loss. The vulnerability is easily exploitable with low attack complexity and no user interaction required.

## Affected products

- Oracle Siebel CRM Deployment 17.0-26.9

## 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 Siebel CRM unauthorized data access in Server Infrastructure](https://junglewise.ai/threats/cve-2026-91450-vulnerability-in-the-siebel-crm-deployment-product-of-oracle)
- [Oracle Siebel CRM Deployment unauthorized data access via HTTP](https://junglewise.ai/threats/cve-2026-91449-vulnerability-in-the-siebel-crm-deployment-product-of-oracle)
- [Oracle Siebel CRM Deployment unauthenticated data access](https://junglewise.ai/threats/cve-2026-91448-vulnerability-in-the-siebel-crm-deployment-product-of-oracle)
- [Oracle Siebel CRM Deployment unauthorized data access](https://junglewise.ai/threats/cve-2026-91447-vulnerability-in-the-siebel-crm-deployment-product-of-oracle)
- [Oracle Siebel CRM privilege escalation in Server Infrastructure](https://junglewise.ai/threats/cve-2026-91444-vulnerability-in-the-siebel-crm-deployment-product-of-oracle)