Arista Networks EOS P4Runtime Arbitrary Code Execution (SA0174)

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

include('compat.inc');

if (description)
{
  script_id(346257);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/09/17");

  script_cve_id("CVE-2026-73453");

  script_name(english:"Arista Networks EOS P4Runtime Arbitrary Code Execution (SA0174)");

  script_set_attribute(attribute:"synopsis", value:
"The version of Arista Networks EOS running on the remote device is affected by a code injection vulnerability.");
  script_set_attribute(attribute:"description", value:
"The version of Arista Networks EOS running on the remote device is affected by a code injection vulnerability as
referenced in security advisory SA0174.

  - An unauthenticated P4Runtime (Programming Protocol-Independent Packet Processors Runtime) client can achieve
    arbitrary code execution under certain conditions on affected platforms running Arista EOS configured with
    P4Runtime. By crafting a malicious packet during the initiation of a P4Runtime session, an attacker can obtain
    complete administrative control over the compromised switch. (CVE-2026-73453)

Note that P4Runtime is disabled by default in Arista EOS. Nessus has not checked the P4Runtime configuration and has
instead relied only on the application's self-reported version number.");
  # https://www.arista.com/en/support/advisories-notices/security-advisory/24730-security-advisory-0174
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?f41c0251");
  script_set_attribute(attribute:"solution", value:
"Upgrade to Arista Networks EOS 4.34.8M / 4.35.6M / 4.36.2F or later, or apply the mitigation referenced in the
vendor advisory.");
  script_set_cvss_base_vector("CVSS2#AV:N/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:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss4_vector", value:"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:U");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-73453");

  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:"2026/09/09");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/09/09");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/09/16");

  script_set_attribute(attribute:"potential_vulnerability", value:"true");
  script_set_attribute(attribute:"plugin_type", value:"combined");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:arista:eos");
  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("arista_eos_detect.nbin");
  script_require_keys("Host/Arista-EOS/Version", "Settings/ParanoidReport");

  exit(0);
}

include('arista_eos_func.inc');
include('audit.inc');

# P4Runtime is disabled by default and the advisory's exposure is gated entirely on it being explicitly enabled.
# That configuration cannot be confirmed from the version alone, so require paranoid reporting.
if (report_paranoia < 2)
  audit(AUDIT_PARANOID);

var version = get_kb_item_or_exit('Host/Arista-EOS/Version');

# The advisory's affected-platform list covers every EOS-based product (all physical switch series plus CloudEOS,
# cEOS-lab, vEOS-lab, the AWE series and CloudVision eXchange), so no model gating is applied here. The products on
# the not-affected list (Wi-Fi APs, CloudVision Portal/CUE/AGNI, DMF, NDR, ETM, NetVisor, VeloCloud) do not run EOS
# and therefore never register Host/Arista-EOS/Version.
var vmatrix = make_array();

# Affected Software, per SA0174. The 4.29.x train is affected only from 4.29.2F onward, so 4.29.0/4.29.1 and every
# release below 4.29.2 are deliberately left out of range. The 4.30.x through 4.33.x trains are affected in their
# entirety ("All releases in the ... train") and have no fix listed. The 4.34.x/4.35.x/4.36.x caps are the last
# affected release named by the advisory, extended to cover intra-release maintenance builds (e.g. 4.34.7.1M) that
# fall below the fix named in the advisory's Resolution section.
vmatrix['all'] = make_list('4.29.2<=4.29.9999',
                           '4.30.0<=4.30.9999',
                           '4.31.0<=4.31.9999',
                           '4.32.0<=4.32.9999',
                           '4.33.0<=4.33.9999',
                           '4.34.0<=4.34.7.9999',
                           '4.35.0<=4.35.5.9999',
                           '4.36.0<=4.36.1.9999');
vmatrix['fix'] = '4.34.8M / 4.35.6M / 4.36.2F';

if (eos_is_affected(vmatrix:vmatrix, version:version))
  security_report_v4(severity:SECURITY_HOLE, port:0, extra:eos_report_get());
else
  audit(AUDIT_INST_VER_NOT_VULN, 'Arista Networks EOS', version);