EulerOS 2.0 SP15 : openssh (EulerOS-SA-2026-2496)

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

include('compat.inc');

if (description)
{
  script_id(323215);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/06/27");

  script_cve_id(
    "CVE-2026-3497",
    "CVE-2026-35385",
    "CVE-2026-35386",
    "CVE-2026-35387",
    "CVE-2026-35388",
    "CVE-2026-35414"
  );
  script_xref(name:"IAVA", value:"2026-A-0296");

  script_name(english:"EulerOS 2.0 SP15 : openssh (EulerOS-SA-2026-2496)");

  script_set_attribute(attribute:"synopsis", value:
"The remote EulerOS host is missing multiple security updates.");
  script_set_attribute(attribute:"description", value:
"According to the versions of the openssh packages installed, the EulerOS installation on the remote host is affected by
the following vulnerabilities :

    OpenSSH before 10.3 omits connection multiplexing confirmation for proxy-mode multiplexing
    sessions.(CVE-2026-35388)

    OpenSSH before 10.3 mishandles the authorized_keys principals option in uncommon scenarios involving a
    principals list in conjunction with a Certificate Authority that makes certain use of comma
    characters.(CVE-2026-35414)

    In OpenSSH before 10.3, command execution can occur via shell metacharacters in a username within a
    command line. This requires a scenario where the username on the command line is untrusted, and also
    requires a non-default configurations of % in ssh_config.(CVE-2026-35386)

    In OpenSSH before 10.3, a file downloaded by scp may be installed setuid or setgid, an outcome contrary to
    some users' expectations, if the download is performed as root with -O (legacy scp protocol) and without
    -p (preserve mode).(CVE-2026-35385)

    OpenSSH before 10.3 can use unintended ECDSA algorithms. Listing of any ECDSA algorithm in
    PubkeyAcceptedAlgorithms or HostbasedAcceptedAlgorithms is misinterpreted to mean all ECDSA
    algorithms.(CVE-2026-35387)

    Vulnerability in the OpenSSH GSSAPI delta included in various Linux distributions. This vulnerability
    affects the GSSAPI patches added by various Linux distributions and does not affect the OpenSSH upstream
    project itself. The usage of sshpkt_disconnect() on an error, which does not terminate the process, allows
    an attacker to send an unexpected GSSAPI message type during the GSSAPI key exchange to the server, which
    will call the underlying function and continue the execution of the program without setting the related
    connection variables. As the variables are not initialized to NULL the code later accesses those
    uninitialized variables, accessing random memory, which could lead to undefined behavior. The recommended
    workaround is to use ssh_packet_disconnect() instead, which does terminate the process. The impact of the
    vulnerability depends heavily on the compiler flag hardening configuration.(CVE-2026-3497)

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

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  # https://developer.huaweicloud.com/ict/en/site-euleros/euleros/security-advisories/EulerOS-SA-2026-2496
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?080ec820");
  script_set_attribute(attribute:"solution", value:
"Update the affected openssh packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:H/Au:N/C:C/I:C/A:C");
  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:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss4_vector", value:"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:U");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-35414");
  script_set_attribute(attribute:"cvss4_score_source", value:"CVE-2026-3497");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/03/12");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/06/26");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/06/27");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:openssh");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:openssh-clients");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:openssh-help");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:openssh-server");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:pam_ssh_agent_auth");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:huawei:euleros:2.0");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Huawei Local Security Checks");

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

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/cpu", "Host/EulerOS/release", "Host/EulerOS/rpm-list", "Host/EulerOS/sp");
  script_exclude_keys("Host/EulerOS/uvp_version");

  exit(0);
}

include("rpm.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);

var _release = get_kb_item("Host/EulerOS/release");
if (isnull(_release) || _release !~ "^EulerOS") audit(AUDIT_OS_NOT, "EulerOS");
var uvp = get_kb_item("Host/EulerOS/uvp_version");
if (_release !~ "^EulerOS release 2\.0(\D|$)") audit(AUDIT_OS_NOT, "EulerOS 2.0 SP15");

var sp = get_kb_item("Host/EulerOS/sp");
if (isnull(sp) || sp !~ "^(15)$") audit(AUDIT_OS_NOT, "EulerOS 2.0 SP15");

if (!empty_or_null(uvp)) audit(AUDIT_OS_NOT, "EulerOS 2.0 SP15", "EulerOS UVP " + uvp);

if (!get_kb_item("Host/EulerOS/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

var cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$" && "aarch64" >!< cpu && "x86" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "EulerOS", cpu);
if ("aarch64" >!< cpu) audit(AUDIT_ARCH_NOT, "aarch64", cpu);

var flag = 0;

var pkgs = [
  "openssh-9.6p1-3.h21510.23.eulerosv2r15",
  "openssh-clients-9.6p1-3.h21510.23.eulerosv2r15",
  "openssh-help-9.6p1-3.h21510.23.eulerosv2r15",
  "openssh-server-9.6p1-3.h21510.23.eulerosv2r15",
  "pam_ssh_agent_auth-0.10.4-5.3.h21510.23.eulerosv2r15"
];

foreach (var pkg in pkgs)
  if (rpm_check(release:"EulerOS-2.0", sp:"15", reference:pkg)) flag++;

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  var tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "openssh");
}