CVE-2026-8727: Tomasnorre/crawler Remote Code Execution Vulnerability

HIGH
Advisory Identifier: GHSA-jr8m-x4p7-p3v5
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CWE-502
Published
Advisory Summary

CVE-2026-8727 is a HIGH remote code execution vulnerability (CWE-502: Deserialization of Untrusted Data) affecting Tomasnorre/crawler libraries in the Packagist ecosystem. The issue involves typo3 remote code execution in extension "site crawler" (crawler). Remediation is available by upgrading affected packages to version 12.0.11, 11.0.13.

CVE-2026-8727 at a Glance

CVE Identifier CVE-2026-8727
GHSA Identifier GHSA-jr8m-x4p7-p3v5
Severity HIGH
CVSS v3.1 Base Score N/A
CWE Classification CWE-502: Deserialization of Untrusted Data
Affected Product Tomasnorre/crawler
Package Ecosystem Packagist
Published Date
Last Updated

How to Fix CVE-2026-8727

To remediate this vulnerability, upgrade all affected Tomasnorre/crawler dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

tomasnorre/crawler fixed: 12.0.11 
Upgrade tomasnorre/crawler to 12.0.11
tomasnorre/crawler fixed: 11.0.13 
Upgrade tomasnorre/crawler to 11.0.13
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for tomasnorre/crawler

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-8727, inspect your project dependencies for Tomasnorre/crawler:

inspect dependencies for tomasnorre/crawler

Analyze the terminal output to locate any version of Tomasnorre/crawler in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 12.0.11), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-502: Deserialization of Untrusted Data, where the product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid. In Tomasnorre/crawler, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

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.

CVE-2026-8727 Affected Tomasnorre/crawler Versions

2 component(s)
Fixed Versions:
12.0.1111.0.13
Product / Package Ecosystem Affected Versions Fixed Version
tomasnorre/crawler
 Packagist
≥ 12.0.0
< 12.0.11
12.0.11
tomasnorre/crawler
 Packagist
< 11.0.13
11.0.13

References

NVD — CVE-2026-8727 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-8727
Tomasnorre/crawler Source Repository REPOSITORY
https://github.com/FriendsOfPHP/security-advisories/blob/master/tomasnorre/crawler/CVE-2026-8727.yaml
Tomasnorre/crawler Source Repository REPOSITORY
https://github.com/tomasnorre/crawler
Tomasnorre/crawler Security Information SECURITY
https://typo3.org/security/advisory/typo3-ext-sa-2026-008

Frequently Asked Questions

What is CVE-2026-8727?
CVE-2026-8727 is a security vulnerability in Tomasnorre/crawler involving TYPO3 Remote Code Execution in extension "Site Crawler" (crawler) under CWE-502: Deserialization of Untrusted Data.
Which Tomasnorre/crawler versions are affected?
Affected versions include releases prior to 12.0.11, 11.0.13 across affected packages: tomasnorre/crawler.
What version fixes CVE-2026-8727?
Upgrading to 12.0.11, 11.0.13 (or the latest patched release for your respective branch) resolves the vulnerability.
Is tomasnorre/crawler affected?
Yes, tomasnorre/crawler is affected in releases prior to 12.0.11, 11.0.13. Upgrade your dependency to 12.0.11, 11.0.13 or later.
What CWE is associated with CVE-2026-8727?
CVE-2026-8727 is classified under CWE-502: Deserialization of Untrusted Data (The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.).
How can I check Packagist dependencies for CVE-2026-8727?
Run the dependency tree command: 'inspect dependencies for tomasnorre/crawler'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-jr8m-x4p7-p3v5",
  "modified" : "2026-06-29T17:39:15Z",
  "published" : "2026-05-19T12:31:39Z",
  "aliases" : [ "CVE-2026-8727" ],
  "summary" : "TYPO3 Remote Code Execution in extension \"Site Crawler\" (crawler)",
  "details" : "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.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:A/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "tomasnorre/crawler"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "12.0.0"
      }, {
        "fixed" : "12.0.11"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "tomasnorre/crawler"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "11.0.13"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-8727"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/FriendsOfPHP/security-advisories/blob/master/tomasnorre/crawler/CVE-2026-8727.yaml"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/tomasnorre/crawler"
  }, {
    "type" : "WEB",
    "url" : "https://typo3.org/security/advisory/typo3-ext-sa-2026-008"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-502" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-06-29T17:39:15Z",
    "nvd_published_at" : "2026-05-19T10:16:25Z"
  }
}