CVE-2026-5426 (GCVE-0-2026-5426)

Vulnerability from cvelistv5 – Published: 2026-04-16 15:18 – Updated: 2026-05-27 14:53
VLAI KEVintel KEV
Title
KnowledgeDeliver deployments before February 24, 2026 use a static ASP.NET/IIS machineKey value
Summary
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
Severity
9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
  • CWE-321 - Use of hard-coded cryptographic key
  • CWE-502 - Deserialization of untrusted data
Assigner
References
Impacted products
Vendor Product Version
Digital Knowledge KnowledgeDeliver Affected: 0 , < 20260224 (date)
Create a notification for this product.
KEVintel KEV
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: 31ec02fb-65ac-46a6-a0c0-f704604579d7

Vulnerability ID: CVE-2026-5426

Status: Confirmed

Status Updated: 2026-05-25 07:00 UTC

Exploited: Yes

Timestamps
First Seen: 2026-05-25
Asserted: 2026-05-25
Scope
Notes: KEVIntel entry: KnowledgeDeliver deployments before February 24, 2026 use a static ASP.NET/IIS machineKey value | Affected: Digital Knowledge / KnowledgeDeliver | CVSS: 9.1 (CRITICAL) | EPSS: 0.0081 | Used in malware: unknown | Not yet in CISA KEV: True
Evidence

Type: Public Report

Signal: Successful Exploitation

Confidence: 70%

Source: kevintel

Details
Feed KEVIntel (kevintel.com)
Title KnowledgeDeliver deployments before February 24, 2026 use a static ASP.NET/IIS machineKey value
Vendor Digital Knowledge
Product KnowledgeDeliver
Added Date 2026-05-25T07:00:00.000Z
Cvss Score 9.1
Epss Score 0.0081
Cvss Severity CRITICAL
Epss Percentile 0.52104
Used In Malware unknown
Ahead Of Cisa Kev None
Not Yet In Cisa Kev True
References
Created: 2026-06-19 12:45 UTC | Updated: 2026-06-19 12:45 UTC
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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