Remote Code Execution Vulnerability in TYPO3 Crawler Extension
CVE-2026-8727

7.1HIGH

Key Information:

Vendor

Typo3

Status
Extension "site Crawler"
Vendor
CVE Published:
19 May 2026

What is CVE-2026-8727?

The TYPO3 Crawler Extension is vulnerable due to the direct handling of the X-T3Crawler-Meta response header with PHP's unserialize() function. This flaw allows an attacker to inject maliciously crafted serialized PHP objects from a controlled endpoint, potentially leading to Remote Code Execution on the TYPO3 server. Exploitation necessitates that the attacker has administrative access to configure a crawler-enabled page and initiate the crawling process through Scheduler tasks.

Affected Version(s)

Extension "Site Crawler" 12.0.0 < 12.0.11

Extension "Site Crawler" 0 < 11.0.13

References

https://typo3.org/security/advisory/typo3-ext-sa-2026-008
vendor-advisory

CVSS V4

Score:
7.1
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
High
Attack Required:
Physical
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Roman Hergenreder
Tomas Norre Mikkelsen
.