EulerOS 2.0 SP11 : python-pyasn1 (EulerOS-SA-2026-4279)

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

include('compat.inc');

if (description)
{
  script_id(364998);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/12");

  script_cve_id("CVE-2026-59884", "CVE-2026-59885", "CVE-2026-59886");

  script_name(english:"EulerOS 2.0 SP11 : python-pyasn1 (EulerOS-SA-2026-4279)");

  script_set_attribute(attribute:"synopsis", value:
"The remote EulerOS host is missing multiple security updates.");
  script_set_attribute(attribute:"description", value:
"According to the versions of the python-pyasn1 packages installed, the EulerOS installation on the remote host is
affected by the following vulnerabilities :

    pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.4, the univ.Real type converted its mantissa,
    base, and exponent value to a Python float using exact big-integer exponentiation. A BER, CER, or DER
    encoded REAL value only a few bytes long can carry a very large exponent, causing float conversion through
    prettyPrint(), str(), comparison, arithmetic, int(), or an explicit float() call to consume excessive CPU
    and memory and hang applications that decode untrusted ASN.1 data and then print, log, or compare decoded
    objects. This issue is fixed in version 0.6.4.(CVE-2026-59886)

    pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.4, the BER decoder shared by the CER and DER
    codecs parses long-form tags by accumulating continuation octets without an upper bound on the tag ID
    size, allowing a crafted input to force construction of an arbitrarily large integer with CPU cost growing
    quadratically and to trigger unhandled ValueError exceptions in Python 3.11+ error formatting paths. Any
    application decoding untrusted BER, CER, or DER input is affected. This issue is fixed in version
    0.6.4.(CVE-2026-59884)

    pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.4, the BER, CER, and DER decoders process
    OBJECT IDENTIFIER and RELATIVE-OID values in quadratic time relative to the number of arcs, so a small
    crafted payload containing an OID with many arcs consumes excessive CPU per decode() call and can deny
    service to applications that decode untrusted ASN.1 data. The corresponding encoders have the same
    quadratic behavior when an application re-encodes previously decoded attacker-supplied values. This issue
    is fixed in version 0.6.4.(CVE-2026-59885)

Tenable has extracted the preceding description block directly from the EulerOS python-pyasn1 security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  # https://developer.huaweicloud.com/ict/en/site-euleros/euleros/security-advisories/EulerOS-SA-2026-4279
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?825fb7f4");
  script_set_attribute(attribute:"solution", value:
"Update the affected python-pyasn1 packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/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:U/C:N/I:N/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-2026-59886");

  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:"2026/07/14");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/10/10");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/10/12");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:python-pyasn1-help");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:python3-pyasn1");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:huawei:euleros:2.0");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

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

  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");
  script_require_keys("Host/local_checks_enabled", "Host/cpu", "Host/EulerOS/release", "Host/EulerOS/rpm-list", "Host/EulerOS/sp");
  script_exclude_keys("Host/EulerOS/uvp_version");

  exit(0);
}

include("rpm.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);

var _release = get_kb_item("Host/EulerOS/release");
if (isnull(_release) || _release !~ "^EulerOS") audit(AUDIT_OS_NOT, "EulerOS");
var uvp = get_kb_item("Host/EulerOS/uvp_version");
if (_release !~ "^EulerOS release 2\.0(\D|$)") audit(AUDIT_OS_NOT, "EulerOS 2.0 SP11");

var sp = get_kb_item("Host/EulerOS/sp");
if (isnull(sp) || sp !~ "^(11)$") audit(AUDIT_OS_NOT, "EulerOS 2.0 SP11");

if (!empty_or_null(uvp)) audit(AUDIT_OS_NOT, "EulerOS 2.0 SP11", "EulerOS UVP " + uvp);

if (!get_kb_item("Host/EulerOS/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

var cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$" && "aarch64" >!< cpu && "x86" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "EulerOS", cpu);

var flag = 0;

var pkgs = [
  "python-pyasn1-help-0.4.8-3.h3.eulerosv2r11",
  "python3-pyasn1-0.4.8-3.h3.eulerosv2r11"
];

foreach (var pkg in pkgs)
  if (rpm_check(release:"EulerOS-2.0", sp:"11", reference:pkg)) flag++;

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  var tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "python-pyasn1");
}