CVE-2026-8727: TYPO3 Remote Code Execution in extension "Site Crawler" (crawler)

May 19, 2026 (updated June 29, 2026)

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.

References

github.com/FriendsOfPHP/security-advisories/blob/master/tomasnorre/crawler/CVE-2026-8727.yaml
github.com/advisories/GHSA-jr8m-x4p7-p3v5
nvd.nist.gov/vuln/detail/CVE-2026-8727
typo3.org/security/advisory/typo3-ext-sa-2026-008

Code Behaviors & Features

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