CVE-2009-0816 — typo3/cms
CVE-2009-0816 is a Cross-site Scripting (XSS) vulnerability in typo3/cms. A fix is available for typo3/cms — see the affected versions and patch details below.
Typo3 Backend XSS Vulnerability
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
typo3/cms🐘typo3/cms🐘typo3/cms🐘typo3/cms🐘typo3/cmsReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
An Information Disclosure vulnerability in jumpUrl mechanism, used to track access on web pages and provided files, allows a remote attacker to read arbitrary files on a host.
The expected value of a mandatory hash secret, intended to invalidate such requests, is exposed to remote users allowing them to bypass access control by providing the correct value.
There's no authentication required to exploit this vulnerability. The vulnerability allows to read any file, the web server user account has access to.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | typo3/cms | ≥ 3.3.0 | No fix |
| 🐘Packagist | typo3/cms | ≥ 4.0&&< 4.0.12 | 4.0.12composer require typo3/cms:^4.0.12 |
| 🐘Packagist | typo3/cms | ≥ 4.1.0&&< 4.1.10 | 4.1.10composer require typo3/cms:^4.1.10 |
| 🐘Packagist | typo3/cms | ≥ 4.2.0&&< 4.2.6 | 4.2.6composer require typo3/cms:^4.2.6 |
| 🐘Packagist | typo3/cms | all versions | No fix |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for typo3/cms, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
No patched version of typo3/cms has shipped for CVE-2009-0816 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2009-0816 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2009-0816. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2009-0816 in your dependencies?
O3 Security finds CVE-2009-0816 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.