Lucene search

K
nessusThis script is Copyright (C) 2021-2023 and is owned by Tenable, Inc. or an Affiliate thereof.EULEROS_SA-2021-2539.NASL
HistorySep 27, 2021 - 12:00 a.m.

EulerOS 2.0 SP9 : python-lxml (EulerOS-SA-2021-2539)

2021-09-2700:00:00
This script is Copyright (C) 2021-2023 and is owned by Tenable, Inc. or an Affiliate thereof.
www.tenable.com
8

4.3 Medium

CVSS2

Attack Vector

NETWORK

Attack Complexity

MEDIUM

Authentication

NONE

Confidentiality Impact

NONE

Integrity Impact

PARTIAL

Availability Impact

NONE

AV:N/AC:M/Au:N/C:N/I:P/A:N

6.1 Medium

CVSS3

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

REQUIRED

Scope

CHANGED

Confidentiality Impact

LOW

Integrity Impact

LOW

Availability Impact

NONE

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

7 High

AI Score

Confidence

High

0.002 Low

EPSS

Percentile

61.7%

According to the versions of the python-lxml package installed, the EulerOS installation on the remote host is affected by the following vulnerabilities :

  • An XSS vulnerability was discovered in python-lxml’s clean module versions before 4.6.3. When disabling the safe_attrs_only and forms arguments, the Cleaner class does not remove the formaction attribute allowing for JS to bypass the sanitizer. A remote attacker could exploit this flaw to run arbitrary JS code on users who interact with incorrectly sanitized HTML. This issue is patched in lxml 4.6.3.
    (CVE-2021-28957)

Note that Tenable Network Security has extracted the preceding description block directly from the EulerOS security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

#%NASL_MIN_LEVEL 70300
##
# (C) Tenable Network Security, Inc.
##

include('deprecated_nasl_level.inc');
include('compat.inc');

if (description)
{
  script_id(153722);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/11/29");

  script_cve_id("CVE-2021-28957");

  script_name(english:"EulerOS 2.0 SP9 : python-lxml (EulerOS-SA-2021-2539)");

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

  - An XSS vulnerability was discovered in python-lxml's clean module versions before 4.6.3. When disabling
    the safe_attrs_only and forms arguments, the Cleaner class does not remove the formaction attribute
    allowing for JS to bypass the sanitizer. A remote attacker could exploit this flaw to run arbitrary JS
    code on users who interact with incorrectly sanitized HTML. This issue is patched in lxml 4.6.3.
    (CVE-2021-28957)

Note that Tenable Network Security has extracted the preceding description block directly from the EulerOS security
advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional
issues.");
  # https://developer.huaweicloud.com/ict/en/site-euleros/euleros/security-advisories/EulerOS-SA-2021-2539
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?54fbfe80");
  script_set_attribute(attribute:"solution", value:
"Update the affected python-lxml packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:N/I:P/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-28957");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2021/03/21");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/09/27");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/09/27");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:python3-lxml");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:huawei:euleros:2.0");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2021-2023 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/EulerOS/release", "Host/EulerOS/rpm-list", "Host/EulerOS/sp");
  script_exclude_keys("Host/EulerOS/uvp_version");

  exit(0);
}

include("audit.inc");
include("global_settings.inc");
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 SP9");

var sp = get_kb_item("Host/EulerOS/sp");
if (isnull(sp) || sp !~ "^(9)$") audit(AUDIT_OS_NOT, "EulerOS 2.0 SP9");

if (!empty_or_null(uvp)) audit(AUDIT_OS_NOT, "EulerOS 2.0 SP9", "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) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "EulerOS", cpu);
if ("aarch64" >!< cpu) audit(AUDIT_ARCH_NOT, "aarch64", cpu);

var flag = 0;

var pkgs = [
  "python3-lxml-4.2.3-4.h3.eulerosv2r9"
];

foreach (var pkg in pkgs)
  if (rpm_check(release:"EulerOS-2.0", sp:"9", reference:pkg)) flag++;

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    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-lxml");
}
VendorProductVersionCPE
huaweieulerospython3-lxmlp-cpe:/a:huawei:euleros:python3-lxml
huaweieuleros2.0cpe:/o:huawei:euleros:2.0

4.3 Medium

CVSS2

Attack Vector

NETWORK

Attack Complexity

MEDIUM

Authentication

NONE

Confidentiality Impact

NONE

Integrity Impact

PARTIAL

Availability Impact

NONE

AV:N/AC:M/Au:N/C:N/I:P/A:N

6.1 Medium

CVSS3

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

REQUIRED

Scope

CHANGED

Confidentiality Impact

LOW

Integrity Impact

LOW

Availability Impact

NONE

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

7 High

AI Score

Confidence

High

0.002 Low

EPSS

Percentile

61.7%