CVE-2026-56855

HighCVSS 7.5/10Last modified Sep 4, 2026

Description

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection. Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

Metrics

CVSS 3.1 7.5/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness enumeration

Affected software

No affected versions have been published.

Timeline

Published
Sep 2, 2026
Last modified
Sep 4, 2026
NVD status
Analyzed

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CVE-2026-56855: High severity, CVSS 7.5 | Vulnix