GHSA-8c28-5mp7-v24h is a medium-severity (CVSS 5.9) CWE-674 vulnerability in typo3/cms-core. A fix is available for typo3/cms-core — see the affected versions and patch details below.
TYPO3 CMS vulnerable to Denial of Service in Page Error Handling
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-8c28-5mp7-v24h.
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.
How urgent is this, really
GHSA-8c28-5mp7-v24h plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,567 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
typo3/cms-core🐘typo3/cms-core🐘typo3/cms-core🐘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
Problem
Requesting invalid or non-existing resources via HTTP triggers the page error handler, which again could retrieve content to be shown as an error message from another page. This leads to a scenario in which the application is calling itself recursively - amplifying the impact of the initial attack until the limits of the web server are exceeded.
This vulnerability is very similar, but not identical, to the one described in TYPO3-CORE-SA-2021-005 (CVE-2021-21359).
Solution
Update to TYPO3 versions 9.5.38 ELTS, 10.4.33 or 11.5.20 that fix the problem described above.
References
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | typo3/cms-core | ≥ 9.0.0&&< 9.5.38 | 9.5.38composer require typo3/cms-core:^9.5.38 |
| 🐘Packagist | typo3/cms-core | ≥ 10.0.0&&< 10.4.33 | 10.4.33composer require typo3/cms-core:^10.4.33 |
| 🐘Packagist | typo3/cms-core | ≥ 11.0.0&&< 11.5.20 | 11.5.20composer require typo3/cms-core:^11.5.20 |
| 🐘Packagist | typo3/cms | ≥ 10.0.0&&< 10.4.33 | 10.4.33composer require typo3/cms:^10.4.33 |
| 🐘Packagist | typo3/cms | ≥ 11.0.0&&< 11.5.20 | 11.5.20composer require typo3/cms:^11.5.20 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for typo3/cms-core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update typo3/cms-core to 9.5.38 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-8c28-5mp7-v24h is resolved across your whole dependency graph.
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 GHSA-8c28-5mp7-v24h can be triaged on real exposure rather than presence alone.
Tailored to GHSA-8c28-5mp7-v24h. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-8c28-5mp7-v24h in your dependencies?
O3 Security finds GHSA-8c28-5mp7-v24h across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.