OpenSSH < 10.5 Multiple Vulnerabilities

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##

include('compat.inc');

if (description)
{
  script_id(335161);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/08/14");

  script_cve_id("CVE-2026-73281", "CVE-2026-73282", "CVE-2026-73283");

  script_name(english:"OpenSSH < 10.5 Multiple Vulnerabilities");

  script_set_attribute(attribute:"synopsis", value:
"The SSH server running on the remote host is affected by multiple vulnerabilities.");
  script_set_attribute(attribute:"description", value:
"The version of OpenSSH installed on the remote host is prior to 10.5. It is, therefore, affected by multiple
vulnerabilities as referenced in the release-10.5 advisory.

  - In ssh in OpenSSH before 10.5, a use-after-free for realloc data can occur if a certain pair of
    remote-forwarding operations are concurrent. (CVE-2026-73282)

  - In ssh-agent in OpenSSH before 10.5, some operations can occur remotely but were intended to occur only
    locally, including operations that add tokens or use keys. This is caused by misinteraction between agent
    locking and the [email protected] extension. (CVE-2026-73281)

  - In sshd in OpenSSH before 10.5, the restrict keyword (in authorized_keys) was supposed to be applicable to
    tunnel forwarding but was not. (CVE-2026-73283)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://www.openssh.com/txt/release-10.5");
  script_set_attribute(attribute:"solution", value:
"Upgrade to OpenSSH version 10.5 or later.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:H/Au:N/C:P/I:P/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-73282");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");
  script_cwe_id(416, 669, 670);

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/08/11");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/08/11");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/08/13");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:openbsd:openssh");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Misc.");

  script_copyright(english:"This script is Copyright (C) 2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("openssh_detect.nbin");
  script_require_keys("installed_sw/OpenSSH");
  script_require_ports("Services/ssh", 22);

  exit(0);
}

include('backport.inc');
include('vcf.inc');
include('vcf_extras.inc');

var port = get_service(svc:'ssh', default:22, exit_on_fail:TRUE);
var app_info = vcf::openssh::get_app_info(app:'OpenSSH', port:port);

vcf::check_all_backporting(app_info:app_info);

var constraints = [
  {'fixed_version': '10.5'}
];

vcf::openssh::check_version_and_report(app_info:app_info, constraints:constraints, severity:SECURITY_WARNING);