Deserialization in Digital Knowledge Knowledgedeliver

CVE-2026-5426

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

EPSS: 0.010 (59.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2026-5426?
CVE-2026-5426 is a critical-severity vulnerability in Digital Knowledge Knowledgedeliver, classified under Use of Hard-coded Cryptographic Key. CVSS score: 9.1/10. Published 2026-04-16.
How severe is CVE-2026-5426?
Critical severity. CVSS v3 base score is 9.1 out of 10.
Is CVE-2026-5426 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.