Linux Distros Unpatched Vulnerability : CVE-2026-4867

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

include('compat.inc');

if (description)
{
  script_id(303899);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/03/30");

  script_cve_id("CVE-2026-4867");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-4867");

  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.

  - Impact: A bad regular expression is generated any time you have three or more parameters within a single
    segment, separated by something that is not a period (.). For example, /:a-:b-:c or /:a-:b-:c-:d. The
    backtrack protection added in [email protected] only prevents ambiguity for two parameters. With three
    or more, the generated lookahead does not block single separator characters, so capture groups overlap and
    cause catastrophic backtracking. Patches: Upgrade to [email protected] Custom regex patterns in route
    definitions (e.g., /:a-:b([^-/]+)-:c([^-/]+)) are not affected because they override the default capture
    group. Workarounds: All versions can be patched by providing a custom regular expression for parameters
    after the first in a single segment. As long as the custom regular expression does not match the text
    before the parameter, you will be safe. For example, change /:a-:b-:c to /:a-:b([^-/]+)-:c([^-/]+). If
    paths cannot be rewritten and versions cannot be upgraded, another alternative is to limit the URL length.
    (CVE-2026-4867)

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-2026-4867");
  script_set_attribute(attribute:"see_also", value:"https://ubuntu.com/security/CVE-2026-4867");
  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:N/I:N/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:U/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:U/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-4867");

  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:"2026/03/26");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/03/26");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04:-:lts");
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  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:20.04:-:lts");
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  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:gjs-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:mozjs60");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:mozjs60-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:pcs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:pcs-snmp");
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  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:sgx-mpa");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:sgx-pckid-tool");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:tdx-qgs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:gjs");
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  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");
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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/CentOS/rpm-list")) && 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 = {
  "Ubuntu Linux-16.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "16.04",
        "pkgs": [
          {"reference": "node-path-to-regexp"}
        ]
      }
    ]
  },
  "Ubuntu Linux-18.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "18.04",
        "pkgs": [
          {"reference": "node-path-to-regexp"}
        ]
      }
    ]
  },
  "Ubuntu Linux-20.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "20.04",
        "pkgs": [
          {"reference": "node-path-to-regexp"}
        ]
      }
    ]
  },
  "Red Hat Enterprise Linux-10": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "10",
        "pkgs": [
          {"reference": "sgx-common"},
          {"reference": "sgx-libs"},
          {"reference": "sgx-mpa"},
          {"reference": "sgx-pckid-tool"},
          {"reference": "tdx-qgs"}
        ]
      }
    ]
  },
  "CentOS Linux-8": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "8",
        "pkgs": [
          {"reference": "mozjs60"},
          {"reference": "mozjs60-devel"},
          {"reference": "pcs"},
          {"reference": "pcs-snmp"}
        ]
      }
    ]
  },
  "Red Hat Enterprise Linux-8": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "8",
        "pkgs": [
          {"reference": "mozjs60"},
          {"reference": "mozjs60-devel"},
          {"reference": "pcs"},
          {"reference": "pcs-snmp"}
        ]
      }
    ]
  },
  "Red Hat Enterprise Linux-9": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "9",
        "pkgs": [
          {"reference": "gjs"},
          {"reference": "gjs-devel"},
          {"reference": "pcs"},
          {"reference": "pcs-snmp"},
          {"reference": "sgx-common"},
          {"reference": "sgx-libs"},
          {"reference": "sgx-mpa"},
          {"reference": "sgx-pckid-tool"},
          {"reference": "tdx-qgs"}
        ]
      }
    ]
  }
};

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