EulerOS Virtualization 2.11.0 : openssh (EulerOS-SA-2026-3534)

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

include('compat.inc');

if (description)
{
  script_id(348057);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/09/18");

  script_cve_id(
    "CVE-2025-26465",
    "CVE-2025-32728",
    "CVE-2025-61984",
    "CVE-2025-61985",
    "CVE-2026-3497",
    "CVE-2026-35385",
    "CVE-2026-35386",
    "CVE-2026-35387",
    "CVE-2026-35388",
    "CVE-2026-35414"
  );
  script_xref(name:"IAVA", value:"2025-A-0126");
  script_xref(name:"IAVA", value:"2025-A-0258-S");
  script_xref(name:"IAVA", value:"2025-A-0729-S");
  script_xref(name:"IAVA", value:"2025-A-0806-S");
  script_xref(name:"IAVA", value:"2026-A-0296-S");

  script_name(english:"EulerOS Virtualization 2.11.0 : openssh (EulerOS-SA-2026-3534)");

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

    A vulnerability was found in OpenSSH when the VerifyHostKeyDNS option is enabled. A machine-in-the-middle
    attack can be performed by a malicious machine impersonating a legit server. This issue occurs due to how
    OpenSSH mishandles error codes in specific conditions when verifying the host key. For an attack to be
    considered successful, the attacker needs to manage to exhaust the client's memory resource first, turning
    the attack complexity high.(CVE-2025-26465)

    In sshd in OpenSSH before 10.0, the DisableForwarding directive does not adhere to the documentation
    stating that it disables X11 and agent forwarding.(CVE-2025-32728)

    ssh in OpenSSH before 10.1 allows control characters in usernames that originate from certain possibly
    untrusted sources, potentially leading to code execution when a ProxyCommand is used. The untrusted
    sources are the command line and %-sequence expansion of a configuration file. (A configuration file that
    provides a complete literal username is not categorized as an untrusted source.)(CVE-2025-61984)

    ssh in OpenSSH before 10.1 allows the '\0' character in an ssh:// URI, potentially leading to code
    execution when a ProxyCommand is used.(CVE-2025-61985)

    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, 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)

    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)

    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)

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

    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 Virtualization 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-2026-3534
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?15e746cb");
  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:POC/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:P/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:P");
  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:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2023/12/12");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/09/16");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/09/18");

  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-server");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:huawei:euleros:uvp:2.11.0");
  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/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 (uvp != "2.11.0") audit(AUDIT_OS_NOT, "EulerOS Virtualization 2.11.0");
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$" && "aarch64" >!< cpu && "x86" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "EulerOS", cpu);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$" && "x86" >!< cpu) audit(AUDIT_ARCH_NOT, "i686 / x86_64", cpu);

var flag = 0;

var pkgs = [
  "openssh-8.8p1-2.h47.eulerosv2r11",
  "openssh-clients-8.8p1-2.h47.eulerosv2r11",
  "openssh-server-8.8p1-2.h47.eulerosv2r11"
];

foreach (var pkg in pkgs)
  if (rpm_check(release:"EulerOS-2.0", 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");
}