What is CVE-2026-8727?

CVE-2026-8727 is a high-severity insecure deserialization vulnerability in tomasnorre/crawler (composer), affecting versions >= 12.0.0, < 12.0.11. It is fixed in 12.0.11, 11.0.13. Untrusted serialized data is processed by a deserializer that can instantiate arbitrary objects or execute code as a side effect.

Which versions of tomasnorre/crawler are affected by CVE-2026-8727?

tomasnorre/crawler (composer) versions >= 12.0.0, < 12.0.11 is affected.

Is there a fix for CVE-2026-8727?

Yes. CVE-2026-8727 is fixed in 12.0.11, 11.0.13. Upgrade to this version or later.

Is CVE-2026-8727 exploitable, and should I be worried?

Whether CVE-2026-8727 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

What actually determines whether CVE-2026-8727 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

CVE-2026-8727 in tomasnorre/crawler

Q: Which versions of tomasnorre/crawler are affected by CVE-2026-8727?

tomasnorre/crawler (composer) versions >= 12.0.0, < 12.0.11 is affected.

Q: Is there a fix for CVE-2026-8727?

Yes. CVE-2026-8727 is fixed in 12.0.11, 11.0.13. Upgrade to this version or later.

Q: Is CVE-2026-8727 exploitable, and should I be worried?

Whether CVE-2026-8727 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

Q: What actually determines whether CVE-2026-8727 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

Q: How do I fix CVE-2026-8727?

Upgrade: tomasnorre/crawler to 12.0.11 or later, tomasnorre/crawler to 11.0.13 or later.

Summary

TYPO3 Remote Code Execution in extension "Site Crawler" (crawler)

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.

Impact

Untrusted serialized data is processed by a deserializer that can instantiate arbitrary objects or execute code as a side effect. Typical impact: arbitrary code execution or logic abuse.

Affected versions

tomasnorre/crawler (>= 12.0.0, < 12.0.11) tomasnorre/crawler (< 11.0.13)

Security releases

tomasnorre/crawler → 12.0.11 (composer) tomasnorre/crawler → 11.0.13 (composer)

Kodem intelligence

Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.

Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.

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Remediation advice

Upgrade the following packages to resolve this vulnerability:

tomasnorre/crawler to 12.0.11 or later; tomasnorre/crawler to 11.0.13 or later

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently Asked Questions

What is CVE-2026-8727? CVE-2026-8727 is a high-severity insecure deserialization vulnerability in tomasnorre/crawler (composer), affecting versions >= 12.0.0, < 12.0.11. It is fixed in 12.0.11, 11.0.13. Untrusted serialized data is processed by a deserializer that can instantiate arbitrary objects or execute code as a side effect.
Which versions of tomasnorre/crawler are affected by CVE-2026-8727? tomasnorre/crawler (composer) versions >= 12.0.0, < 12.0.11 is affected.
Is there a fix for CVE-2026-8727? Yes. CVE-2026-8727 is fixed in 12.0.11, 11.0.13. Upgrade to this version or later.
Is CVE-2026-8727 exploitable, and should I be worried? Whether CVE-2026-8727 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
What actually determines whether CVE-2026-8727 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
How do I fix CVE-2026-8727?
- Upgrade tomasnorre/crawler to 12.0.11 or later
- Upgrade tomasnorre/crawler to 11.0.13 or later