CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
EPSS
Percentile
60.9%
The remote Fedora 35 host has a package installed that is affected by a vulnerability as referenced in the FEDORA-2022-76b3530ac2 advisory.
phpCAS::setUrl()
is called (a reminder that you have to pass in the full URL of the current page, rather than your service base URL), and 2. phpCAS::setCallbackURL()
is called, only when the proxy mode is enabled. 3. If your PHP’s HTTP header input X-Forwarded-Host
, X-Forwarded- Server
, Host
, X-Forwarded-Proto
, X-Forwarded-Protocol
is sanitized before reaching PHP (by a reverse proxy, for example), you will not be impacted by this vulnerability either. If your CAS server service registry is configured to only allow known and trusted service URLs the severity of the vulnerability is reduced substantially in its severity since an attacker must be in control of another authorized service. Otherwise, you should upgrade the library to get the safe service discovery behavior.Note that Nessus has not tested for this issue but has instead relied only on the application’s self-reported version number.
#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##
# The descriptive text and package checks in this plugin were
# extracted from Fedora Security Advisory FEDORA-2022-76b3530ac2
#
include('compat.inc');
if (description)
{
script_id(169203);
script_version("1.0");
script_set_attribute(attribute:"plugin_modification_date", value:"2022/12/23");
script_cve_id("CVE-2022-39369");
script_xref(name:"FEDORA", value:"2022-76b3530ac2");
script_name(english:"Fedora 35 : php-pear-CAS (2022-76b3530ac2)");
script_set_attribute(attribute:"synopsis", value:
"The remote Fedora host is missing one or more security updates.");
script_set_attribute(attribute:"description", value:
"The remote Fedora 35 host has a package installed that is affected by a vulnerability as referenced in the
FEDORA-2022-76b3530ac2 advisory.
- phpCAS is an authentication library that allows PHP applications to easily authenticate users via a
Central Authentication Service (CAS) server. The phpCAS library uses HTTP headers to determine the service
URL used to validate tickets. This allows an attacker to control the host header and use a valid ticket
granted for any authorized service in the same SSO realm (CAS server) to authenticate to the service
protected by phpCAS. Depending on the settings of the CAS server service registry in worst case this may
be any other service URL (if the allowed URLs are configured to ^(https)://.*) or may be strictly
limited to known and authorized services in the same SSO federation if proper URL service validation is
applied. This vulnerability may allow an attacker to gain access to a victim's account on a vulnerable
CASified service without victim's knowledge, when the victim visits attacker's website while being logged
in to the same CAS server. phpCAS 1.6.0 is a major version upgrade that starts enforcing service URL
discovery validation, because there is unfortunately no 100% safe default config to use in PHP. Starting
this version, it is required to pass in an additional service base URL argument when constructing the
client class. For more information, please refer to the upgrading doc. This vulnerability only impacts the
CAS client that the phpCAS library protects against. The problematic service URL discovery behavior in
phpCAS < 1.6.0 will only be disabled, and thus you are not impacted from it, if the phpCAS configuration
has the following setup: 1. `phpCAS::setUrl()` is called (a reminder that you have to pass in the full URL
of the current page, rather than your service base URL), and 2. `phpCAS::setCallbackURL()` is called, only
when the proxy mode is enabled. 3. If your PHP's HTTP header input `X-Forwarded-Host`, `X-Forwarded-
Server`, `Host`, `X-Forwarded-Proto`, `X-Forwarded-Protocol` is sanitized before reaching PHP (by a
reverse proxy, for example), you will not be impacted by this vulnerability either. If your CAS server
service registry is configured to only allow known and trusted service URLs the severity of the
vulnerability is reduced substantially in its severity since an attacker must be in control of another
authorized service. Otherwise, you should upgrade the library to get the safe service discovery behavior.
(CVE-2022-39369)
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://bodhi.fedoraproject.org/updates/FEDORA-2022-76b3530ac2");
script_set_attribute(attribute:"solution", value:
"Update the affected php-pear-CAS package.");
script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/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:L/UI:R/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-2022-39369");
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:"2022/11/01");
script_set_attribute(attribute:"patch_publication_date", value:"2022/11/03");
script_set_attribute(attribute:"plugin_publication_date", value:"2022/12/23");
script_set_attribute(attribute:"plugin_type", value:"local");
script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:35");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:php-pear-CAS");
script_set_attribute(attribute:"generated_plugin", value:"current");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"Fedora Local Security Checks");
script_copyright(english:"This script is Copyright (C) 2022 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("ssh_get_info.nasl");
script_require_keys("Host/local_checks_enabled", "Host/RedHat/release", "Host/RedHat/rpm-list");
exit(0);
}
include('rpm.inc');
if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_release = get_kb_item('Host/RedHat/release');
if (isnull(os_release) || 'Fedora' >!< os_release) audit(AUDIT_OS_NOT, 'Fedora');
var os_ver = pregmatch(pattern: "Fedora.*release ([0-9]+)", string:os_release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, 'Fedora');
os_ver = os_ver[1];
if (! preg(pattern:"^35([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, 'Fedora 35', 'Fedora ' + os_ver);
if (!get_kb_item('Host/RedHat/rpm-list')) audit(AUDIT_PACKAGE_LIST_MISSING);
var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('x86_64' >!< cpu && cpu !~ "^i[3-6]86$" && 's390' >!< cpu && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Fedora', cpu);
var pkgs = [
{'reference':'php-pear-CAS-1.6.0-1.fc35', 'release':'FC35', 'rpm_spec_vers_cmp':TRUE}
];
var flag = 0;
foreach package_array ( pkgs ) {
var reference = NULL;
var _release = NULL;
var sp = NULL;
var _cpu = NULL;
var el_string = NULL;
var rpm_spec_vers_cmp = NULL;
var epoch = NULL;
var allowmaj = NULL;
if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
if (!empty_or_null(package_array['release'])) _release = package_array['release'];
if (!empty_or_null(package_array['sp'])) sp = package_array['sp'];
if (!empty_or_null(package_array['cpu'])) _cpu = package_array['cpu'];
if (!empty_or_null(package_array['el_string'])) el_string = package_array['el_string'];
if (!empty_or_null(package_array['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = package_array['rpm_spec_vers_cmp'];
if (!empty_or_null(package_array['epoch'])) epoch = package_array['epoch'];
if (!empty_or_null(package_array['allowmaj'])) allowmaj = package_array['allowmaj'];
if (reference && _release) {
if (rpm_check(release:_release, sp:sp, cpu:_cpu, reference:reference, epoch:epoch, el_string:el_string, rpm_spec_vers_cmp:rpm_spec_vers_cmp, allowmaj:allowmaj)) 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, 'php-pear-CAS');
}