CVE-2026-8727
Remote Code Execution in extension "Site Crawler" (crawler)
Description
The 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.
INFO
Published Date :
May 19, 2026, 10:16 a.m.
Last Modified :
May 19, 2026, 10:16 a.m.
Remotely Exploit :
Yes !
Source :
f4fb688c-4412-4426-b4b8-421ecf27b14a
Affected Products
The following products are affected by CVE-2026-8727
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | HIGH | f4fb688c-4412-4426-b4b8-421ecf27b14a | ||||
| CVSS 4.0 | HIGH | f4fb688c-4412-4426-b4b8-421ecf27b14a |
Solution
- Disable the X-T3Crawler-Meta header.
- Sanitize input before unserialization.
- Update the Crawler extension.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-8727.
| URL | Resource |
|---|---|
| https://typo3.org/security/advisory/typo3-ext-sa-2026-008 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-8727 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-8727
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-8727 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-8727 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by f4fb688c-4412-4426-b4b8-421ecf27b14a
May. 19, 2026
Action Type Old Value New Value Added Description The 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. Added CVSS V4.0 AV:N/AC:H/AT:P/PR:H/UI:A/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-502 Added Reference https://typo3.org/security/advisory/typo3-ext-sa-2026-008