Detections
Analytics
AlmaLinux 10 : libssh (ALSA-2026:55855)
high Nessus Plugin ID 337665
Synopsis
The remote AlmaLinux host is missing one or more security updates.Description
The remote AlmaLinux 10 host has packages installed that are affected by multiple vulnerabilities as referenced in the ALSA-2026:55855 advisory.* libssh: libssh: information disclosure via short GSSAPI Curve25519 public key (CVE-2026-59842)
* libssh: libssh: denial of service via zero advertised channel packet size (CVE-2026-59843)
* libssh: libssh: denial of service via oversized SFTP read length (CVE-2026-59844)
* libssh: libssh: denial of service via unchecked ProxyCommand fork() failure (CVE-2026-59845)
* libssh: libssh: information disclosure via ProxyCommand %r username expansion (CVE-2026-59846)
* libssh: libssh: integrity downgrade via OpenSSL AES-GCM tag verification (CVE-2026-59847)
* libssh: libssh: denial of service via SFTP responses with unknown request IDs (CVE-2026-59848)
* libssh: libssh: denial of service via automatic certificate authentication loop (CVE-2026-59849)
* libssh: libssh: use-after-free via data callbacks on closed channels (CVE-2026-59850)
* libssh: libssh: authentication bypass via missing GSSAPI principal check (CVE-2026-59851)
* libssh: libssh: stack buffer overflow in SFTP server longname construction (CVE-2026-15370)
Tenable has extracted the preceding description block directly from the AlmaLinux security advisory.
Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.
Solution
Update the affected libssh, libssh-config and / or libssh-devel packages.See Also
Plugin Details
Severity: High
ID: 337665
File Name: alma_linux_ALSA-2026-55855.nasl
Version: 1.1
Type: Local
Family: Alma Linux Local Security Checks
Published: 8/18/2026
Updated: 8/18/2026
Supported Sensors: Nessus Agent, Continuous Assessment, Nessus
Risk Information
VPR
Risk Factor: Medium
Score: 4.9
Percentile: 58.13
CVSS v2
Risk Factor: High
Base Score: 7.8
Temporal Score: 5.8
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:C/A:N
CVSS Score Source: CVE-2026-59847
CVSS v3
Risk Factor: High
Base Score: 7.5
Temporal Score: 6.5
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C
Vulnerability Information
CPE: cpe:/o:alma:linux:10, cpe:/o:alma:linux:10::appstream, cpe:/o:alma:linux:10::baseos, cpe:/o:alma:linux:10::highavailability, cpe:/o:alma:linux:10::nfv, cpe:/o:alma:linux:10::powertools, cpe:/o:alma:linux:10::realtime, cpe:/o:alma:linux:10::resilientstorage, cpe:/o:alma:linux:10::sap, cpe:/o:alma:linux:10::sap_hana, cpe:/o:alma:linux:10::supplementary, p-cpe:/a:alma:linux:libssh-config, p-cpe:/a:alma:linux:libssh-devel, p-cpe:/a:alma:linux:libssh
Required KB Items: Host/local_checks_enabled, Host/cpu, Host/AlmaLinux/release, Host/AlmaLinux/rpm-list
Exploit Ease: No known exploits are available
Patch Publication Date: 8/17/2026
Vulnerability Publication Date: 7/21/2026
Reference Information
CVE: CVE-2026-15370, CVE-2026-59842, CVE-2026-59843, CVE-2026-59844, CVE-2026-59845, CVE-2026-59846, CVE-2026-59847, CVE-2026-59848, CVE-2026-59849, CVE-2026-59850, CVE-2026-59851