# TYPO3 CMS vulnerable to Denial of Service in Page Error Handling Advisory record · `GHSA-8c28-5mp7-v24h` - **Identifiers:** `GHSA-8c28-5mp7-v24h` · `BIT-typo3-2022-23500` · `CVE-2022-23500` · `PKSA-j3x1-dtrb-kbct` · `PKSA-wh51-qtyw-9mq5` - **State:** Confirmed - **Severity:** CVSS 5.9 Medium - **Critical:** No - **Weakness (CWE):** [CWE-405](https://cwe.mitre.org/data/definitions/405.html) · [CWE-674](https://cwe.mitre.org/data/definitions/674.html) - **Tags:** [Denial of service](https://agentprime.io/advisories/tag/dos.md) · [CWE-405](https://agentprime.io/advisories/tag/cwe-405.md) - **Published:** 13 Dec 2022 - **Updated:** 6 Dec 2023 - **Reviewed by a person:** No Published by the GitHub Advisory Database at 13 Dec 2022, 17:02 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. ## Affected packages - `typo3/cms-core` (Packagist): affected `>=9.0.0, <9.5.38 || >=10.0.0, <10.4.33 || >=11.0.0, <11.5.20`; fixed in `9.5.38`, `10.4.33`, `11.5.20` - `typo3/cms` (Packagist): affected `>=10.0.0, <10.4.33 || >=11.0.0, <11.5.20`; fixed in `10.4.33`, `11.5.20` ## Machine-written summary Summary written by Claude Haiku from the source advisory. Not reviewed by a person. > TYPO3 CMS packages typo3/cms-core (versions 9.0.0 to before 9.5.38, 10.0.0 to before 10.4.33, and 11.0.0 to before 11.5.20) and typo3/cms (versions 10.0.0 to before 10.4.33 and 11.0.0 to before 11.5.20) are affected. An attacker who can send HTTP requests for invalid or non-existing resources can trigger the page error handler to call the application recursively, which can exhaust the web server's limits and cause denial of service. Upgrade typo3/cms-core to 9.5.38, 10.4.33 or 11.5.20, and typo3/cms to 10.4.33 or 11.5.20. Written 5 Nov 2026. ## Not analysed yet We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check. ## Severity and exploitation - 5.9 Medium, CVSS 3.1: `CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H`, from CNA (GitHub_M) - **CISA KEV:** Not listed. - **EPSS:** 0.0073, the 54th percentile, on 6 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days. ## Timeline - 31 Oct 2026, 14:32 UTC: First seen by agentprime - 31 Oct 2026, 14:32 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-8c28-5mp7-v24h) ## Sources - [GitHub Advisory Database: GHSA-8c28-5mp7-v24h](https://github.com/advisories/GHSA-8c28-5mp7-v24h) - [OSV: GHSA-8c28-5mp7-v24h](https://osv.dev/vulnerability/GHSA-8c28-5mp7-v24h) - - - - - - - Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code. ## Check whether this affects you A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet. - With the agentprime MCP server (), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: - In a browser: reads your lockfile in the browser, never uploading it. - Whether it touches your code, with file and line: the Claude Code plugin, - As JSON: , or `POST https://api.agentprime.io/v1/match` with your packages () --- The web page: . Everything for agents: .