Juniper Junos OS Multiple Local Privilege Escalation Vulnerabilities (JSA11114)

##
# (C) Tenable Network Security, Inc.
##

include('compat.inc');

if (description)
{
  script_id(145502);
  script_version("1.5");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/01/25");

  script_cve_id("CVE-2021-0204", "CVE-2021-0223");
  script_xref(name:"JSA", value:"JSA11114");
  script_xref(name:"IAVA", value:"2021-A-0036-S");

  script_name(english:"Juniper Junos OS Multiple Local Privilege Escalation Vulnerabilities (JSA11114)");

  script_set_attribute(attribute:"synopsis", value:
"The remote device is missing a vendor-supplied security patch.");
  script_set_attribute(attribute:"description", value:
"The version of Junos OS installed on the remote host is affected by multiple local privilege escalation
vulnerabilities as referenced in the JSA11114 advisory. Specifically:

  - A sensitive information disclosure vulnerability in delta-export configuration utility (dexp) of Juniper
    Networks Junos OS may allow a locally authenticated shell user the ability to create and read database
    files generated by the dexp utility, including password hashes of local users. Since dexp is shipped with
    setuid permissions enabled and is owned by the root user, this vulnerability may allow a local privileged
    user the ability to run dexp with root privileges and access sensitive information in the dexp database.
    (CVE-2021-0204)
    
  - A local privilege escalation vulnerability in telnetd.real of Juniper Networks Junos OS may allow a locally
    authenticated shell user to escalate privileges and execute arbitrary commands as root. telnetd.real is 
    shipped with setuid permissions enabled and is owned by the root user, allowing local users to run telnetd.real
    with root privileges. (CVE-2021-0223)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported
version number.");
  script_set_attribute(attribute:"see_also", value:"https://kb.juniper.net/JSA11114");
  script_set_attribute(attribute:"solution", value:
"Apply the relevant Junos software release referenced in Juniper advisory JSA11114");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-0223");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2021/01/13");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/01/13");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/01/27");

  script_set_attribute(attribute:"plugin_type", value:"combined");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:juniper:junos");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Junos Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2021-2024 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("junos_version.nasl");
  script_require_keys("Host/Juniper/JUNOS/Version");

  exit(0);
}

include('junos.inc');

ver = get_kb_item_or_exit('Host/Juniper/JUNOS/Version');

vuln_ranges = [
  {'min_ver':'1.0','fixed_ver':'15.1R7-S9'},
  {'min_ver':'17.3', 'fixed_ver':'17.3R3-S11'},
  {'min_ver':'17.4', 'fixed_ver':'17.4R2-S12'},
  {'min_ver':'17.4R3', 'fixed_ver':'17.4R3-S3'},
  {'min_ver':'18.1', 'fixed_ver':'18.1R3-S11'},
  {'min_ver':'18.2', 'fixed_ver':'18.2R3-S6'},
  {'min_ver':'18.3', 'fixed_ver':'18.3R3-S4'},
  {'min_ver':'18.4', 'fixed_ver':'18.4R2-S7'},
  {'min_ver':'18.4R3', 'fixed_ver':'18.4R3-S6'},
  {'min_ver':'19.1', 'fixed_ver':'19.1R2-S2'},
  {'min_ver':'19.1R3', 'fixed_ver':'19.1R3-S4'},
  {'min_ver':'19.2', 'fixed_ver':'19.2R1-S6'},
  {'min_ver':'19.2R2', 'fixed_ver':'19.2R3-S1'},
  {'min_ver':'19.3', 'fixed_ver':'19.3R3-S1'},
  {'min_ver':'19.4', 'fixed_ver':'19.4R2-S2'},
  {'min_ver':'19.4R3', 'fixed_ver':'19.4R3-S1'},
  {'min_ver':'20.1', 'fixed_ver':'20.1R1-S4', 'fixed_display': '20.1R1-S4, 20.1R2'},
  {'min_ver':'20.2', 'fixed_ver':'20.2R2'}
];

fix = junos_compare_range(target_version:ver, vuln_ranges:vuln_ranges);
if (empty_or_null(fix)) audit(AUDIT_INST_VER_NOT_VULN, 'Junos OS', ver);
report = get_report(ver:ver, fix:fix);
security_report_v4(severity:SECURITY_HOLE, port:0, extra:report);