Linux Distros Unpatched Vulnerability : CVE-2026-16615

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

include('compat.inc');

if (description)
{
  script_id(329440);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/07/25");

  script_cve_id("CVE-2026-16615");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-16615");

  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.

  - A flaw was found in librest. The PKCE implementation for OAuth authorization uses the GRand function from
    the GLib API, a cryptographically insecure pseudo-random number generator. Because the generated code
    verifier lacks sufficient cryptographic entropy, a malicious actor can reverse-engineer the pseudo-random
    number generator (PRNG) seed to predict or reconstruct the code verifier string, allowing an attacker to
    bypass PKCE protections and successfully impersonate the client during the OAuth 2.0 authorization flow.
    (CVE-2026-16615)

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-2026-16615");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2026-16615");
  script_set_attribute(attribute:"see_also", value:"https://ubuntu.com/security/CVE-2026-16615");
  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:L/Au:N/C:P/I:P/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:U/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:U/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-16615");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/07/22");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/07/25");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:20.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:22.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:24.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:26.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:11.0");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:12.0");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:13.0");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:14.0");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:10");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:librest");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:librest");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:rest");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:rest-devel");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  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("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/Debian Linux-11", "Host/OS/Debian Linux-12", "Host/OS/Debian Linux-13", "Host/OS/Debian Linux-14", "Host/OS/Red Hat Enterprise Linux-10", "Host/OS/Ubuntu Linux-16.04", "Host/OS/Ubuntu Linux-18.04", "Host/OS/Ubuntu Linux-20.04", "Host/OS/Ubuntu Linux-22.04", "Host/OS/Ubuntu Linux-24.04", "Host/OS/Ubuntu Linux-26.04");

  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/Debian/dpkg-l")) && empty_or_null(get_one_kb_item("Host/RedHat/rpm-list"))) audit(AUDIT_PACKAGE_LIST_MISSING);

include('linux_unpatched.inc');

var distro_constraints_array = {
  "Debian Linux-12": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "12",
        "pkgs": [
          {"reference": "gir1.2-rest-1.0"},
          {"reference": "gir1.2-restextras-1.0"},
          {"reference": "librest-1.0-0"},
          {"reference": "librest-dev"},
          {"reference": "librest-doc"},
          {"reference": "librest-extras-1.0-0"},
          {"reference": "librest-extras-dev"}
        ]
      }
    ]
  },
  "Debian Linux-13": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "13",
        "pkgs": [
          {"reference": "gir1.2-rest-1.0"},
          {"reference": "gir1.2-restextras-1.0"},
          {"reference": "librest-1.0-0"},
          {"reference": "librest-dev"},
          {"reference": "librest-doc"},
          {"reference": "librest-extras-1.0-0"},
          {"reference": "librest-extras-dev"}
        ]
      }
    ]
  },
  "Debian Linux-14": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "14",
        "pkgs": [
          {"reference": "gir1.2-rest-1.0"},
          {"reference": "gir1.2-restextras-1.0"},
          {"reference": "librest-1.0-0"},
          {"reference": "librest-dev"},
          {"reference": "librest-doc"},
          {"reference": "librest-extras-1.0-0"},
          {"reference": "librest-extras-dev"}
        ]
      }
    ]
  },
  "Ubuntu Linux-24.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "24.04",
        "pkgs": [
          {"reference": "gir1.2-rest-1.0"},
          {"reference": "gir1.2-restextras-1.0"},
          {"reference": "librest-1.0-0"},
          {"reference": "librest-dev"},
          {"reference": "librest-doc"},
          {"reference": "librest-extras-1.0-0"},
          {"reference": "librest-extras-dev"}
        ]
      }
    ]
  },
  "Ubuntu Linux-26.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "26.04",
        "pkgs": [
          {"reference": "gir1.2-rest-1.0"},
          {"reference": "gir1.2-restextras-1.0"},
          {"reference": "librest-1.0-0"},
          {"reference": "librest-dev"},
          {"reference": "librest-doc"},
          {"reference": "librest-extras-1.0-0"},
          {"reference": "librest-extras-dev"}
        ]
      }
    ]
  },
  "Debian Linux-11": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "11",
        "pkgs": [
          {"reference": "gir1.2-rest-0.7"},
          {"reference": "gir1.2-restextras-0.7"},
          {"reference": "librest-0.7-0"},
          {"reference": "librest-dev"},
          {"reference": "librest-doc"},
          {"reference": "librest-extras-0.7-0"},
          {"reference": "librest-extras-dev"}
        ]
      }
    ]
  },
  "Ubuntu Linux-20.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "20.04",
        "pkgs": [
          {"reference": "gir1.2-rest-0.7"},
          {"reference": "gir1.2-restextras-0.7"},
          {"reference": "librest-0.7-0"},
          {"reference": "librest-dev"},
          {"reference": "librest-doc"},
          {"reference": "librest-extras-0.7-0"},
          {"reference": "librest-extras-dev"}
        ]
      }
    ]
  },
  "Ubuntu Linux-22.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "22.04",
        "pkgs": [
          {"reference": "gir1.2-rest-0.7"},
          {"reference": "gir1.2-restextras-0.7"},
          {"reference": "librest-0.7-0"},
          {"reference": "librest-dev"},
          {"reference": "librest-doc"},
          {"reference": "librest-extras-0.7-0"},
          {"reference": "librest-extras-dev"}
        ]
      }
    ]
  },
  "Ubuntu Linux-16.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "16.04",
        "pkgs": [
          {"reference": "gir1.2-rest-0.7"},
          {"reference": "gir1.2-rest-extras-0.7"},
          {"reference": "librest-0.7-0"},
          {"reference": "librest-0.7-0-dbg"},
          {"reference": "librest-dev"},
          {"reference": "librest-doc"},
          {"reference": "librest-extras-0.7-0"},
          {"reference": "librest-extras-dev"}
        ]
      }
    ]
  },
  "Ubuntu Linux-18.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "18.04",
        "pkgs": [
          {"reference": "gir1.2-rest-0.7"},
          {"reference": "gir1.2-rest-extras-0.7"},
          {"reference": "librest-0.7-0"},
          {"reference": "librest-0.7-0-dbg"},
          {"reference": "librest-dev"},
          {"reference": "librest-doc"},
          {"reference": "librest-extras-0.7-0"},
          {"reference": "librest-extras-dev"}
        ]
      }
    ]
  },
  "Red Hat Enterprise Linux-10": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "10",
        "pkgs": [
          {"reference": "rest"},
          {"reference": "rest-devel"}
        ]
      }
    ]
  }
};

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 third_party_support = get_kb_item('Host/OS/extended-third-party');
if (!empty_or_null(third_party_support)) {
    var third_party_vendors = distro_constraints_values['third_party'];
    if (!empty_or_null(third_party_vendors)) {
        var vendor;
        foreach vendor (third_party_vendors) {
            if (vendor == third_party_support) exit(0, 'A third party management patch is available for this vulnerability from ' + vendor + '.\n');
        }
    }
}

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_WARNING,
      extra      : report
  );
  exit(0);
}
else
{
  audit(AUDIT_HOST_NOT, 'affected');
}