Linux Distros Unpatched Vulnerability : CVE-2026-15806

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

include('compat.inc');

if (description)
{
  script_id(338038);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/08/19");

  script_cve_id("CVE-2026-15806");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-15806");

  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.

  - The HTTPPasswordMgr class in the urllib.request module, along with its subclasses
    HTTPPasswordMgrWithDefaultRealm and HTTPPasswordMgrWithPriorAuth, did not take the URL scheme into account
    when matching stored credentials against a requested URL. Credentials added for an https:// URL were also
    used for requests to the same host over http://, so an attacker able to redirect or downgrade a client to
    plain HTTP (for example, via an HTTPS-to-HTTP redirect or an on-path position) could capture credentials
    in cleartext. Credentials added for http:// URLs could likewise be sent over https://. Credential matching
    is now scoped by URL scheme. Credentials registered with a URL that includes a scheme are only used for
    requests with the same scheme. Credentials registered with a bare authority (such as example.com or
    example.com:8080) continue to match any scheme, preserving compatibility with existing code, including
    proxy authentication. Users who cannot upgrade immediately can mitigate by ensuring that applications
    never make plain http:// requests to hosts for which credentials are registered, for example by not
    following redirects to http:// URLs. (CVE-2026-15806)

Note that Nessus relies on the presence of the package as reported by the vendor.");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2026-15806");
  script_set_attribute(attribute:"see_also", value:"https://ubuntu.com/security/CVE-2026-15806");
  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:P/I:N/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:C/C:H/I:L/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:U/RC:C");
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  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:U");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-15806");

  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:"2026/08/18");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/08/19");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:14.04:-:lts");
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  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");
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  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python3.11");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python3.12");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python3.14");
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  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python3.9");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:pypy3");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:python2.7");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:python3.11");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:python3.13");
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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");
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  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"))) 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": "idle-python3.11"},
          {"reference": "libpython3.11"},
          {"reference": "libpython3.11-dbg"},
          {"reference": "libpython3.11-dev"},
          {"reference": "libpython3.11-minimal"},
          {"reference": "libpython3.11-stdlib"},
          {"reference": "libpython3.11-testsuite"},
          {"reference": "pypy3"},
          {"reference": "pypy3-dev"},
          {"reference": "pypy3-doc"},
          {"reference": "pypy3-lib"},
          {"reference": "pypy3-lib-testsuite"},
          {"reference": "pypy3-tk"},
          {"reference": "pypy3-venv"},
          {"reference": "python3.11"},
          {"reference": "python3.11-dbg"},
          {"reference": "python3.11-dev"},
          {"reference": "python3.11-doc"},
          {"reference": "python3.11-examples"},
          {"reference": "python3.11-full"},
          {"reference": "python3.11-minimal"},
          {"reference": "python3.11-nopie"},
          {"reference": "python3.11-venv"}
        ]
      }
    ]
  },
  "Debian Linux-11": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "11",
        "pkgs": [
          {"reference": "idle-python2.7"},
          {"reference": "idle-python3.9"},
          {"reference": "libpython2.7"},
          {"reference": "libpython2.7-dbg"},
          {"reference": "libpython2.7-dev"},
          {"reference": "libpython2.7-minimal"},
          {"reference": "libpython2.7-stdlib"},
          {"reference": "libpython2.7-testsuite"},
          {"reference": "libpython3.9"},
          {"reference": "libpython3.9-dbg"},
          {"reference": "libpython3.9-dev"},
          {"reference": "libpython3.9-minimal"},
          {"reference": "libpython3.9-stdlib"},
          {"reference": "libpython3.9-testsuite"},
          {"reference": "pypy3"},
          {"reference": "pypy3-dev"},
          {"reference": "pypy3-doc"},
          {"reference": "pypy3-lib"},
          {"reference": "pypy3-lib-testsuite"},
          {"reference": "pypy3-tk"},
          {"reference": "python2.7"},
          {"reference": "python2.7-dbg"},
          {"reference": "python2.7-dev"},
          {"reference": "python2.7-doc"},
          {"reference": "python2.7-examples"},
          {"reference": "python2.7-minimal"},
          {"reference": "python3.9"},
          {"reference": "python3.9-dbg"},
          {"reference": "python3.9-dev"},
          {"reference": "python3.9-doc"},
          {"reference": "python3.9-examples"},
          {"reference": "python3.9-full"},
          {"reference": "python3.9-minimal"},
          {"reference": "python3.9-venv"}
        ]
      }
    ]
  },
  "Debian Linux-14": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "14",
        "pkgs": [
          {"reference": "idle-python3.13"},
          {"reference": "idle-python3.14"},
          {"reference": "idle-python3.15"},
          {"reference": "libpython3.13"},
          {"reference": "libpython3.13-dbg"},
          {"reference": "libpython3.13-dev"},
          {"reference": "libpython3.13-minimal"},
          {"reference": "libpython3.13-stdlib"},
          {"reference": "libpython3.13-testsuite"},
          {"reference": "libpython3.14"},
          {"reference": "libpython3.14-dbg"},
          {"reference": "libpython3.14-dev"},
          {"reference": "libpython3.14-minimal"},
          {"reference": "libpython3.14-stdlib"},
          {"reference": "libpython3.14-testsuite"},
          {"reference": "libpython3.15"},
          {"reference": "libpython3.15-dbg"},
          {"reference": "libpython3.15-dev"},
          {"reference": "libpython3.15-minimal"},
          {"reference": "libpython3.15-stdlib"},
          {"reference": "libpython3.15-testsuite"},
          {"reference": "pypy3"},
          {"reference": "pypy3-dev"},
          {"reference": "pypy3-doc"},
          {"reference": "pypy3-lib"},
          {"reference": "pypy3-lib-testsuite"},
          {"reference": "pypy3-tk"},
          {"reference": "pypy3-venv"},
          {"reference": "python3.13"},
          {"reference": "python3.13-dbg"},
          {"reference": "python3.13-dev"},
          {"reference": "python3.13-doc"},
          {"reference": "python3.13-examples"},
          {"reference": "python3.13-full"},
          {"reference": "python3.13-gdbm"},
          {"reference": "python3.13-minimal"},
          {"reference": "python3.13-nopie"},
          {"reference": "python3.13-tk"},
          {"reference": "python3.13-venv"},
          {"reference": "python3.14"},
          {"reference": "python3.14-dbg"},
          {"reference": "python3.14-dev"},
          {"reference": "python3.14-doc"},
          {"reference": "python3.14-examples"},
          {"reference": "python3.14-full"},
          {"reference": "python3.14-gdbm"},
          {"reference": "python3.14-minimal"},
          {"reference": "python3.14-nopie"},
          {"reference": "python3.14-tk"},
          {"reference": "python3.14-venv"},
          {"reference": "python3.15"},
          {"reference": "python3.15-dbg"},
          {"reference": "python3.15-dev"},
          {"reference": "python3.15-doc"},
          {"reference": "python3.15-examples"},
          {"reference": "python3.15-full"},
          {"reference": "python3.15-gdbm"},
          {"reference": "python3.15-minimal"},
          {"reference": "python3.15-nopie"},
          {"reference": "python3.15-tk"},
          {"reference": "python3.15-venv"}
        ]
      }
    ]
  },
  "Debian Linux-13": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "13",
        "pkgs": [
          {"reference": "idle-python3.13"},
          {"reference": "libpython3.13"},
          {"reference": "libpython3.13-dbg"},
          {"reference": "libpython3.13-dev"},
          {"reference": "libpython3.13-minimal"},
          {"reference": "libpython3.13-stdlib"},
          {"reference": "libpython3.13-testsuite"},
          {"reference": "pypy3"},
          {"reference": "pypy3-dev"},
          {"reference": "pypy3-doc"},
          {"reference": "pypy3-lib"},
          {"reference": "pypy3-lib-testsuite"},
          {"reference": "pypy3-tk"},
          {"reference": "pypy3-venv"},
          {"reference": "python3.13"},
          {"reference": "python3.13-dbg"},
          {"reference": "python3.13-dev"},
          {"reference": "python3.13-doc"},
          {"reference": "python3.13-examples"},
          {"reference": "python3.13-full"},
          {"reference": "python3.13-gdbm"},
          {"reference": "python3.13-minimal"},
          {"reference": "python3.13-nopie"},
          {"reference": "python3.13-tk"},
          {"reference": "python3.13-venv"}
        ]
      }
    ]
  },
  "Ubuntu Linux-14.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "14.04",
        "pkgs": [
          {"reference": "idle-python2.7"},
          {"reference": "idle-python3.4"},
          {"reference": "libpython2.7"},
          {"reference": "libpython2.7-dbg"},
          {"reference": "libpython2.7-dev"},
          {"reference": "libpython2.7-minimal"},
          {"reference": "libpython2.7-stdlib"},
          {"reference": "libpython2.7-testsuite"},
          {"reference": "libpython3.4"},
          {"reference": "libpython3.4-dbg"},
          {"reference": "libpython3.4-dev"},
          {"reference": "libpython3.4-minimal"},
          {"reference": "libpython3.4-stdlib"},
          {"reference": "libpython3.4-testsuite"},
          {"reference": "python2.7"},
          {"reference": "python2.7-dbg"},
          {"reference": "python2.7-dev"},
          {"reference": "python2.7-doc"},
          {"reference": "python2.7-examples"},
          {"reference": "python2.7-minimal"},
          {"reference": "python3.4"},
          {"reference": "python3.4-dbg"},
          {"reference": "python3.4-dev"},
          {"reference": "python3.4-doc"},
          {"reference": "python3.4-examples"},
          {"reference": "python3.4-minimal"},
          {"reference": "python3.5"}
        ]
      }
    ]
  },
  "Ubuntu Linux-16.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "16.04",
        "pkgs": [
          {"reference": "idle-python2.7"},
          {"reference": "idle-python3.5"},
          {"reference": "libpython2.7"},
          {"reference": "libpython2.7-dbg"},
          {"reference": "libpython2.7-dev"},
          {"reference": "libpython2.7-minimal"},
          {"reference": "libpython2.7-stdlib"},
          {"reference": "libpython2.7-testsuite"},
          {"reference": "libpython3.5"},
          {"reference": "libpython3.5-dbg"},
          {"reference": "libpython3.5-dev"},
          {"reference": "libpython3.5-minimal"},
          {"reference": "libpython3.5-stdlib"},
          {"reference": "libpython3.5-testsuite"},
          {"reference": "python2.7"},
          {"reference": "python2.7-dbg"},
          {"reference": "python2.7-dev"},
          {"reference": "python2.7-doc"},
          {"reference": "python2.7-examples"},
          {"reference": "python2.7-minimal"},
          {"reference": "python3.5"},
          {"reference": "python3.5-dbg"},
          {"reference": "python3.5-dev"},
          {"reference": "python3.5-doc"},
          {"reference": "python3.5-examples"},
          {"reference": "python3.5-minimal"},
          {"reference": "python3.5-venv"}
        ]
      }
    ]
  },
  "Ubuntu Linux-18.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "18.04",
        "pkgs": [
          {"reference": "idle-python2.7"},
          {"reference": "idle-python3.6"},
          {"reference": "libpython2.7"},
          {"reference": "libpython2.7-dbg"},
          {"reference": "libpython2.7-dev"},
          {"reference": "libpython2.7-minimal"},
          {"reference": "libpython2.7-stdlib"},
          {"reference": "libpython2.7-testsuite"},
          {"reference": "libpython3.6"},
          {"reference": "libpython3.6-dbg"},
          {"reference": "libpython3.6-dev"},
          {"reference": "libpython3.6-minimal"},
          {"reference": "libpython3.6-stdlib"},
          {"reference": "libpython3.6-testsuite"},
          {"reference": "python2.7"},
          {"reference": "python2.7-dbg"},
          {"reference": "python2.7-dev"},
          {"reference": "python2.7-doc"},
          {"reference": "python2.7-examples"},
          {"reference": "python2.7-minimal"},
          {"reference": "python3.6"},
          {"reference": "python3.6-dbg"},
          {"reference": "python3.6-dev"},
          {"reference": "python3.6-doc"},
          {"reference": "python3.6-examples"},
          {"reference": "python3.6-minimal"},
          {"reference": "python3.6-venv"},
          {"reference": "python3.7"},
          {"reference": "python3.8"}
        ]
      }
    ]
  },
  "Ubuntu Linux-20.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "20.04",
        "pkgs": [
          {"reference": "idle-python3.8"},
          {"reference": "libpython3.8"},
          {"reference": "libpython3.8-dbg"},
          {"reference": "libpython3.8-dev"},
          {"reference": "libpython3.8-minimal"},
          {"reference": "libpython3.8-stdlib"},
          {"reference": "libpython3.8-testsuite"},
          {"reference": "python2.7"},
          {"reference": "python3.8"},
          {"reference": "python3.8-dbg"},
          {"reference": "python3.8-dev"},
          {"reference": "python3.8-doc"},
          {"reference": "python3.8-examples"},
          {"reference": "python3.8-minimal"},
          {"reference": "python3.8-venv"},
          {"reference": "python3.9"}
        ]
      }
    ]
  },
  "Ubuntu Linux-22.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "22.04",
        "pkgs": [
          {"reference": "idle-python3.10"},
          {"reference": "libpython3.10"},
          {"reference": "libpython3.10-dbg"},
          {"reference": "libpython3.10-dev"},
          {"reference": "libpython3.10-minimal"},
          {"reference": "libpython3.10-stdlib"},
          {"reference": "libpython3.10-testsuite"},
          {"reference": "python2.7"},
          {"reference": "python3.10"},
          {"reference": "python3.10-dbg"},
          {"reference": "python3.10-dev"},
          {"reference": "python3.10-doc"},
          {"reference": "python3.10-examples"},
          {"reference": "python3.10-full"},
          {"reference": "python3.10-minimal"},
          {"reference": "python3.10-nopie"},
          {"reference": "python3.10-venv"},
          {"reference": "python3.11"}
        ]
      }
    ]
  },
  "Ubuntu Linux-24.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "24.04",
        "pkgs": [
          {"reference": "idle-python3.12"},
          {"reference": "libpython3.12-dev"},
          {"reference": "libpython3.12-minimal"},
          {"reference": "libpython3.12-stdlib"},
          {"reference": "libpython3.12-testsuite"},
          {"reference": "libpython3.12t64"},
          {"reference": "libpython3.12t64-dbg"},
          {"reference": "python3.12"},
          {"reference": "python3.12-dbg"},
          {"reference": "python3.12-dev"},
          {"reference": "python3.12-doc"},
          {"reference": "python3.12-examples"},
          {"reference": "python3.12-full"},
          {"reference": "python3.12-minimal"},
          {"reference": "python3.12-nopie"},
          {"reference": "python3.12-venv"}
        ]
      }
    ]
  },
  "Ubuntu Linux-26.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "26.04",
        "pkgs": [
          {"reference": "idle-python3.14"},
          {"reference": "libpython3.14"},
          {"reference": "libpython3.14-dbg"},
          {"reference": "libpython3.14-dev"},
          {"reference": "libpython3.14-minimal"},
          {"reference": "libpython3.14-stdlib"},
          {"reference": "libpython3.14-testsuite"},
          {"reference": "python3.14"},
          {"reference": "python3.14-dbg"},
          {"reference": "python3.14-dev"},
          {"reference": "python3.14-doc"},
          {"reference": "python3.14-examples"},
          {"reference": "python3.14-full"},
          {"reference": "python3.14-gdbm"},
          {"reference": "python3.14-minimal"},
          {"reference": "python3.14-nopie"},
          {"reference": "python3.14-tk"},
          {"reference": "python3.14-venv"}
        ]
      }
    ]
  }
};

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');
}