# ApostropheCMS: POST /api/v1/@apostrophecms/doc/slugTaken discloses existence of private/admin-only content to any authenticated user

Advisory record · `GHSA-f66c-mpj2-3r8h`

- **Identifiers:** `GHSA-f66c-mpj2-3r8h` · `CVE-2026-112952`
- **State:** Confirmed
- **Severity:** CVSS 4.3 Medium
- **Critical:** No
- **Weakness (CWE):** [CWE-200](https://cwe.mitre.org/data/definitions/200.html)
- **Tags:** [Information disclosure](https://agentprime.io/advisories/tag/info-disclosure.md)
- **Published:** 21 Oct 2026
- **Updated:** 21 Oct 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 21 Oct 2026, 17:17 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `apostrophe` (npm): affected `<4.34.0`; fixed in `4.34.0`

## Machine-written summary

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

> ApostropheCMS versions before 4.34.0 (npm package apostrophe) expose a slugTaken API endpoint that reports whether a slug is in use across all document types and visibility levels, without checking the requester's permissions. An attacker needs only a logged-in account, including an editor-level one, and can use repeated requests to learn which private, draft, or archived content exists. Upgrade apostrophe to version 4.34.0 or later.

Written 31 Oct 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

- 4.3 Medium, CVSS 3.1: `CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N`, from CNA (GitHub_M)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0033, the 26th percentile, on 8 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 13:33 UTC: First seen by agentprime
- 31 Oct 2026, 13:33 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-f66c-mpj2-3r8h)

## Sources

- [GitHub Advisory Database: GHSA-f66c-mpj2-3r8h](https://github.com/advisories/GHSA-f66c-mpj2-3r8h)
- [OSV: GHSA-f66c-mpj2-3r8h](https://osv.dev/vulnerability/GHSA-f66c-mpj2-3r8h)
- <https://github.com/apostrophecms/apostrophe/security/advisories/GHSA-f66c-mpj2-3r8h>
- <https://nvd.nist.gov/vuln/detail/CVE-2026-112952>
- <https://github.com/apostrophecms/apostrophe/commit/06e4b377f3c360f9e89c32dccd7e505ad5ddf498>
- <https://github.com/apostrophecms/apostrophe/commit/40b989b1a9dd23d30029b8ce7668634265cfe5ea>
- <https://github.com/apostrophecms/apostrophe>
- <https://github.com/apostrophecms/apostrophe/releases/tag/apostrophe@4.34.0>

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-f66c-mpj2-3r8h>, 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-f66c-mpj2-3r8h/>. Everything for agents: <https://agentprime.io/llms.txt>.