CVE-2026-63234: Three Learning Koollab LMS SQL injection and unsafe deserialization

CVE-2026-63234 · Severity: critical · CVSS 9.9 · Published 2026-07-29

Koollab LMS, a cloud-based learning management system used for corporate training and assessments, contains a critical security flaw. An authorized user, such as a student or instructor, can exploit the manual marking feature to gain full control over the server. This could lead to the theft of sensitive student data, modification of training records, or a complete shutdown of the learning platform.

Technologies: Three Learning Koollab LMS. Vendors: Three Learning.

Quick answers

Is CVE-2026-63234 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-63234 being exploited in the wild.
How severe is CVE-2026-63234?
Critical severity, with a CVSS score of 9.9, published 29 July 2026.
Which products and versions are affected?
Three Learning Koollab LMS 5.3.2.
Is there a fix for CVE-2026-63234?
A patch was published on 2026-04-26: Vendor patched cloud instances Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-63234 attacked?
It is attacked over the network, in a hosted service.
Am I affected by CVE-2026-63234?
Check whether you run Three Learning Koollab LMS 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 critical vulnerability exists in Koollab LMS version 5.3.2 within the manual mark assessment endpoint. The flaw combines SQL injection with unsafe deserialization, where an authenticated attacker can inject malicious payloads to control data passed to the PHP unserialize() function. By leveraging this, an attacker can achieve remote code execution (RCE) and write a webshell to a publicly accessible directory on the server. The vendor, Three Learning, has patched all cloud-hosted instances of this SaaS product, so no manual user action is required.

Affected products

  • Three Learning Koollab LMS 5.3.2

Timeline

  • 2026-04-14: disclosed: Disclosed to vendor
  • 2026-04-26: patched: Vendor patched cloud instances
  • 2026-07-29: advisory: Public release of advisory

References

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