This page tracks the Debian fix status. The vulnerability itself is described on the main CVE page. View CVE-2026-59843 →

DEBIAN-CVE-2026-59843

A flaw was found in libssh. A remote authenticated peer can advertise a zero maximum packet size in SSH_MSG_CHANNEL_OPEN, causing later channel writes...

Original description

The description as published by the source.

A flaw was found in libssh. A remote authenticated peer can advertise a zero maximum packet size in SSH_MSG_CHANNEL_OPEN, causing later channel writes to loop indefinitely and consume CPU, leading to denial of service.

Source: OSV.dev (Open Source Vulnerabilities) OSV

Affected packages

Debian:12 libssh

[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]

Debian:13 libssh

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.11.5-0+deb13u1"}]}]

Debian:14 libssh

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.12.2-1"}]}]

References

advisory security-tracker.debian.org