# Kirby has XML injection in its XML creator toolkit

Advisory record · `GHSA-9wfj-c55w-j9qr`

- **Identifiers:** `GHSA-9wfj-c55w-j9qr` · `CVE-2026-32870` · `PKSA-rr97-2byk-h46m`
- **State:** Confirmed
- **Severity:** CVSS 6.9 Medium
- **Critical:** No
- **Weakness (CWE):** [CWE-91](https://cwe.mitre.org/data/definitions/91.html)
- **Tags:** [Other injection](https://agentprime.io/advisories/tag/injection.md)
- **Published:** 23 Apr 2026
- **Updated:** 5 May 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 23 Apr 2026, 21:21 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `getkirby/cms` (Packagist): affected `<4.9.0 || >=5.0.0, <5.4.0`; fixed in `4.9.0`, `5.4.0`

## Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

> Kirby (getkirby/cms) versions before 4.9.0 and from 5.0.0 before 5.4.0 are affected. The Xml::value() method wrongly let values pass through unescaped when they contained a CDATA block alongside other XML markup, so an attacker who controls input to Xml::create(), Xml::tag(), Xml::value() or the Xml data handler can inject structure into generated XML. Upgrade to Kirby 4.9.0, 5.4.0 or a later version.

Written 3 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

- 6.9 Medium, CVSS 4.0: `CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:H/SA:N`, from CNA (GitHub_M)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0035, the 28th percentile, on 14 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 14:25 UTC: First seen by agentprime
- 31 Oct 2026, 14:25 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-9wfj-c55w-j9qr)

## Sources

- [GitHub Advisory Database: GHSA-9wfj-c55w-j9qr](https://github.com/advisories/GHSA-9wfj-c55w-j9qr)
- [OSV: GHSA-9wfj-c55w-j9qr](https://osv.dev/vulnerability/GHSA-9wfj-c55w-j9qr)
- <https://github.com/getkirby/kirby/security/advisories/GHSA-9wfj-c55w-j9qr>
- <https://nvd.nist.gov/vuln/detail/CVE-2026-32870>
- <https://github.com/getkirby/kirby>
- <https://github.com/getkirby/kirby/releases/tag/4.9.0>
- <https://github.com/getkirby/kirby/releases/tag/5.4.0>

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 (<https://api.agentprime.io/mcp>), 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: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-9wfj-c55w-j9qr>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-9wfj-c55w-j9qr/>. Everything for agents: <https://agentprime.io/llms.txt>.