Squid < 7.6 Heap-based Buffer Overflow

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

include('compat.inc');

if (description)
{
  script_id(321511);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/06/18");

  script_cve_id("CVE-2026-50012");

  script_name(english:"Squid < 7.6 Heap-based Buffer Overflow");

  script_set_attribute(attribute:"synopsis", value:
"The remote proxy server is affected by a heap-based buffer overflow vulnerability.");
  script_set_attribute(attribute:"description", value:
"The version of Squid on the remote host is prior to 7.6. It is, therefore, affected by a heap-based buffer overflow
vulnerability:

  - Due to an Improper Input Validation bug, Squid is vulnerable to a Heap-based Buffer Overflow attack against
    cache digests. This problem allows a trusted server to perform a Heap-based Buffer Overflow when sending
    maliciously crafted replies to cache_digest request messages. This attack is limited to Squid instances that
    have been compiled with the --enable-cache-digests option. (CVE-2026-50012)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
  # https://github.com/squid-cache/squid/commit/19fcfe922717c8b255270c032dcde4071c003bcd.patch
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?c99d5d24");
  script_set_attribute(attribute:"see_also", value:"https://seclists.org/oss-sec/2026/q2/896");
  script_set_attribute(attribute:"solution", value:
"Upgrade to Squid version 7.6 or later.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:P");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-50012");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/06/12");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/06/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/06/18");

  script_set_attribute(attribute:"potential_vulnerability", value:"true");
  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:squid-cache:squid");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Firewalls");

  script_copyright(english:"This script is Copyright (C) 2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("squid_version.nasl");
  script_require_keys("installed_sw/Squid", "Settings/ParanoidReport");
  script_require_ports("Services/http_proxy", 3128, 8080);

  exit(0);
}

include('vdf.inc');

if (report_paranoia < 2)
  audit(AUDIT_PARANOID);

# @tvdl-content
var vuln_data = {
  'metadata': {'spec_version': '1.0'},
  'requires': [
    {'scope': 'target', 'match': {'paranoia': true}}
  ],
  'checks': [
    {
      'product': {'name': 'Squid', 'type': 'app'},
      'check_algorithm': 'default',
      'constraints': [
        {'fixed_version' : '7.6'}
      ]
    }
  ]
};

var result = vdf::check_and_report(vuln_data:vuln_data, severity:SECURITY_WARNING);
vdf::handle_check_and_report_errors(vdf_result:result);