The TYPO3 Crawler extension passes the X-T3Crawler-Meta response header from crawled URLs directly to PHP's unserialize(). An attacker controlling a crawled endpoint can inject arbitrary serialized PHP objects, leading to Remote Code Execution on the TYPO3 server. Exploitation requires administrative privileges to configure a crawler-enabled page and trigger the crawl via a Scheduler task. This has been patched in versions 12.0.11 and 11.0.13.
{
"cwe_ids": [
"CWE-502"
],
"github_reviewed": true,
"github_reviewed_at": "2026-06-29T17:39:15Z",
"nvd_published_at": "2026-05-19T10:16:25Z",
"severity": "HIGH"
}