Linux Distros Unpatched Vulnerability : CVE-2026-41651

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

include('compat.inc');

if (description)
{
  script_id(309713);
  script_version("1.9");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/05/19");

  script_cve_id("CVE-2026-41651");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-41651");

  script_set_attribute(attribute:"synopsis", value:
"The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be
patched.");
  script_set_attribute(attribute:"description", value:
"The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied
patch available.

  - PackageKit is a a D-Bus abstraction layer that allows the user to manage packages in a secure way using a
    cross-distro, cross-architecture API. PackageKit between and including versions 1.0.2 and 1.3.4 is
    vulnerable to a time-of-check time-of-use (TOCTOU) race condition on transaction flags that allows
    unprivileged users to install packages as root and thus leads to a local privilege escalation. This is
    patched in version 1.3.5. A local unprivileged user can install arbitrary RPM packages as root, including
    executing RPM scriptlets, without authentication. The vulnerability is a TOCTOU race condition on
    `transaction->cached_transaction_flags` combined with a silent state-machine guard that discards illegal
    backward transitions while leaving corrupted flags in place. Three bugs exist in `src/pk-transaction.c`:
    1. Unconditional flag overwrite (line 4036): `InstallFiles()` writes caller-supplied flags to
    `transaction->cached_transaction_flags` without checking whether the transaction has already been
    authorized/started. A second call blindly overwrites the flags even while the transaction is RUNNING. 2.
    Silent state-transition rejection (lines 873882): `pk_transaction_set_state()` silently discards backward
    state transitions (e.g. `RUNNING`  `WAITING_FOR_AUTH`) but the flag overwrite at step 1 already happened.
    The transaction continues running with corrupted flags. 3. Late flag read at execution time (lines
    22732277): The scheduler's idle callback reads cached_transaction_flags at dispatch time, not at
    authorization time. If flags were overwritten between authorization and execution, the backend sees the
    attacker's flags. (CVE-2026-41651)

Note that Nessus relies on the presence of the package as reported by the vendor.");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/security/cve/cve-2026-41651");
  script_set_attribute(attribute:"solution", value:
"There is no known solution at this time.");
  script_set_attribute(attribute:"agent", value:"unix");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:U/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:U/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-41651");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"vendor_unpatched", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/04/22");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/04/22");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:centos:centos:7");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:7");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:PackageKit");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:PackageKit-command-not-found");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:PackageKit-cron");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:PackageKit-glib");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:PackageKit-glib-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:PackageKit-gstreamer-plugin");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:PackageKit-gtk3-module");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:PackageKit-yum");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:PackageKit-yum-plugin");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:PackageKit");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:PackageKit-command-not-found");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:PackageKit-cron");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:PackageKit-glib");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:PackageKit-glib-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:PackageKit-gstreamer-plugin");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:PackageKit-gtk3-module");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:PackageKit-yum");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:PackageKit-yum-plugin");
  script_set_attribute(attribute:"generated_plugin", value:"current");
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  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("ssh_get_info2.nasl", "set_linux_os_id.nasl");
  script_require_keys("Host/cpu", "Host/local_checks_enabled", "global_settings/vendor_unpatched", "Host/OS/identifier");
  script_require_ports("Host/OS/CentOS Linux-7", "Host/OS/Red Hat Enterprise Linux-7");

  exit(0);
}

if (!get_kb_item("global_settings/vendor_unpatched")) exit(0, "Unpatched Vulnerabilities Detection not active.");
if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (empty_or_null(get_one_kb_item("Host/CentOS/rpm-list")) && empty_or_null(get_one_kb_item("Host/RedHat/rpm-list"))) audit(AUDIT_PACKAGE_LIST_MISSING);

include('linux_unpatched.inc');

var distro_constraints_array = {
  "CentOS Linux-7": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "7",
        "pkgs": [
          {"reference": "PackageKit"},
          {"reference": "PackageKit-command-not-found"},
          {"reference": "PackageKit-cron"},
          {"reference": "PackageKit-glib"},
          {"reference": "PackageKit-glib-devel"},
          {"reference": "PackageKit-gstreamer-plugin"},
          {"reference": "PackageKit-gtk3-module"},
          {"reference": "PackageKit-yum"},
          {"reference": "PackageKit-yum-plugin"}
        ]
      }
    ]
  },
  "Red Hat Enterprise Linux-7": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "7",
        "pkgs": [
          {"reference": "PackageKit"},
          {"reference": "PackageKit-command-not-found"},
          {"reference": "PackageKit-cron"},
          {"reference": "PackageKit-glib"},
          {"reference": "PackageKit-glib-devel"},
          {"reference": "PackageKit-gstreamer-plugin"},
          {"reference": "PackageKit-gtk3-module"},
          {"reference": "PackageKit-yum"},
          {"reference": "PackageKit-yum-plugin"}
        ]
      }
    ]
  }
};

var distro_constraints_values = linux_unpatched::get_distro_constraints(distro_constraints_arr:distro_constraints_array);
if (empty_or_null(distro_constraints_values)) audit(AUDIT_HOST_NOT, 'affected');
var report = linux_unpatched::check_unpatched_constraints(distro_constraints_values:distro_constraints_values);

if (!empty_or_null(report))
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_HOLE,
      extra      : report
  );
  exit(0);
}
else
{
  audit(AUDIT_HOST_NOT, 'affected');
}