What’s Vulnerable › Vulnerabilities

CVE-2026-5426: KnowledgeDeliver deployments before February 24, 2026 use a static ASP.NET/IIS machineKey value

• Severity: critical (CVSS 9.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.0% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-04-16 · updated 2026-10-26
• Weakness: CWE-321

Description

Hard-coded ASP.NET/IIS machineKey value in Digital Knowledge KnowledgeDeliver deployments prior to February 24, 2026 allows adversaries to circumvent ViewState validation mechanisms and achieve remote code execution via malicious ViewState deserialization attacks

Affected products

• Digital Knowledge KnowledgeDeliver: before 20260224 — fixed in 20260224

How to fix

Upgrade to a fixed version: Digital Knowledge KnowledgeDeliver 20260224. Check the vendor advisory for mitigations.

References

• https://cloud.google.com/blog/topics/threat-intelligence/knowledgedeliver-viewstate-deserialization-vulnerability
• https://github.com/mandiant/Vulnerability-Disclosures/blob/master/2026/MNDT-2026-0009.md
• https://www.digital-knowledge.co.jp/product/kd/

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