Quick answers
- Is CVE-2026-63233 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-63233 being exploited in the wild.
- How severe is CVE-2026-63233?
- 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-2026-63233?
- 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-2026-63233 attacked?
- It is attacked over the network, in a hosted service.
- Am I affected by CVE-2026-63233?
- 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
The vulnerability exists in the 'assessment overall answer' endpoint of Koollab LMS. An authenticated attacker can perform a SQL injection to manipulate data that is subsequently passed to the PHP unserialize() function. By controlling the input to this function, an attacker can achieve remote code execution (RCE) through object injection. This allows the attacker to write a webshell to a publicly accessible directory on the server. The vendor has patched all cloud-hosted instances, and as a SaaS product, no user action is required.
Affected products
- Three Learning Koollab LMS 5.3.2
Timeline
- 2026-04-14: disclosed: Vendor disclosure
- 2026-04-26: patched: Vendor patched cloud instances
- 2026-07-29: advisory: Public release of advisory