The vulnerability is a memory leak in Wikimedia Foundation's Scribunto extension that causes the PHP script runJobs.php to grow memory usage until exhaustion. The flaw is associated with CWE-401 (memory leak) and CWE-79. The leaked memory can accumulate over time, eventually resulting in out-of-memory errors that halt the job queue and disrupt services.

Scribunto versions from 1.45.0 up to, but not including, 1.45.2 are affected. Any deployment of these versions that processes jobs with runJobs.php is susceptible to the leak.

The CVSS score of 2.3 indicates a low severity denial‑of‑service risk, and the EPSS score of <1% suggests a very low likelihood of exploitation. The vulnerability is not listed in CISA KEV. Exploitation requires local control over job submissions or triggering the job queue; no publicly available exploit has been reported. Because it depends on the job queue running continuously, the risk is situational and may be mitigated by limiting concurrency or monitoring memory, but the fundamental flaw remains until the patch is applied. The flaw is associated with CWE‑401 (memory leak) and CWE‑79.