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.

The remote Fedora 43 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2026-063caa9112 advisory.

    New upstream security release (#2503148)


Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Fedora 44 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2026-0e46c91ccf advisory.

    New upstream security release


Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The version of libssh installed on the remote host is prior to 0.11.5 / 0.12.1. It is, therefore, affected by multiple vulnerabilities as referenced in the SSA:2026-202-01 advisory.

    New libssh packages are available for Slackware 15.0 and -current to fix security issues.

Tenable has extracted the preceding description block directly from the libssh security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Severity
329166	Fedora 43 : libssh (2026-063caa9112)	Nessus	Fedora Local Security Checks	medium
329159	Fedora 44 : libssh (2026-0e46c91ccf)	Nessus	Fedora Local Security Checks	high
328881	Slackware Linux 15.0 / current libssh Multiple Vulnerabilities (SSA:2026-202-01)	Nessus	Slackware Local Security Checks	medium

Detections

Analytics

CVE-2026-59843

medium

Tenable Plugins

medium

high

medium