CVE intelligence and bounded remediation

CVE-2021-36231 — Unit4 Mik.Starlight security vulnerability

High CVSS 9

Deserialization of untrusted data in multiple functions in MIK.starlight 7.9.5.24363 allows authenticated remote attackers to execute operating system commands by crafting serialized objects.

Severity
High
CVSS
9 (2.0)
Published
2021-08-31
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-502

Affected products

  • unit4 / mik.starlight / 7.9.5.24363

Matched remediation archetype

Unsafe deserialization and object reconstruction

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Check exposure

  • Inventory serialization formats accepted from requests, queues, caches, files, cookies, and cross-service messages.
  • Trace whether untrusted input can select classes, types, callbacks, constructors, or object hooks during decoding.
  • Identify signing, schema validation, trust-boundary, and compatibility settings for each decoder.

Remediate safely

  • Replace native object deserialization with a data-only format and explicit schema validation.
  • If replacement is not immediate, use a safe decoder with a minimal type allowlist and disable polymorphic or executable hooks.
  • Update the affected library and add inert tests for unknown types, extra fields, malformed nesting, and unsigned data.

Authoritative sources

Complete CVE record and remediation plan

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