# CVE-2026-106585: OpenSSH packet length check bypass in decompression

Source: https://junglewise.ai/threats/cve-2026-106585-in-sshd-and-ssh-in-openssh-before-10-6-there-is-no-check-for  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-06. Updated: 2026-10-06  
License: CC BY 4.0 with a link back

CVE-2026-106585 · Severity: medium · CVSS 6.5 · Published 2026-10-06

OpenSSH, a widely-used remote access tool that allows secure connections to servers, lacks validation of maximum packet sizes when decompressing highly compressed data. An attacker could exploit this to cause a denial of service or potentially execute code by sending specially crafted packets that exceed safe limits.

Technologies: [OpenSSH](https://junglewise.ai/threats/technologies/openssh-openssh). Vendors: [OpenSSH](https://junglewise.ai/threats/vendors/openssh).

## Quick answers

**Is CVE-2026-106585 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-106585 being exploited in the wild.

**How severe is CVE-2026-106585?** Medium severity, with a CVSS score of 6.5, published 6 October 2026.

**Which products and versions are affected?** OpenSSH before 10.6.

**Is there a fix for CVE-2026-106585?** Yes: fixed in OpenSSH 10.6. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-106585 attacked?** It is attacked over the network, in a hosted service.

**Am I affected by CVE-2026-106585?** Check whether you run OpenSSH at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- Fixed in OpenSSH 10.6

## Technical details

The vulnerability exists in the decompression handling of OpenSSH before version 10.6, where no check ensures that decompressed data does not exceed the maximum allowed packet length. This affects both the client (ssh) and server (sshd) components. An attacker with network access to an SSH service can send highly compressed packets that expand beyond protocol limits, potentially triggering buffer overflows or resource exhaustion.

## Affected products

- OpenSSH OpenSSH before 10.6

## Timeline

- 2026-10-06: disclosed

## References

- [https://www.openssh.org/releasenotes.html](https://www.openssh.org/releasenotes.html)

## Related threats

- [OpenSSH password authentication bypass on musl libc without PAM](https://junglewise.ai/threats/cve-2026-123158-sshd-in-openssh-before-10-6p2-on-linux-when-musl-libc-is-used)
- [OpenSSH decompression memory exhaustion](https://junglewise.ai/threats/cve-2026-110927-a-flaw-was-found-in-openssh-after-compression-is-negotiated-a)
- [OpenSSH GSSAPI credential persistence authentication bypass](https://junglewise.ai/threats/cve-2026-110924-a-flaw-was-found-in-openssh-with-gssapi-authentication-enabled-a)
- [OpenSSH compression dictionary information disclosure](https://junglewise.ai/threats/cve-2026-110926-a-flaw-was-found-in-openssh-when-compression-is-negotiated)
- [OpenSSH shell metacharacter injection in ProxyCommand](https://junglewise.ai/threats/cve-2026-110925-a-flaw-was-found-in-openssh-a-username-entered-on-the-ssh)