CVSS2
Attack Vector
ADJACENT_NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:A/AC:L/Au:N/C:N/I:N/A:P
CVSS3
Attack Vector
ADJACENT
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
AI Score
Confidence
High
EPSS
Percentile
68.3%
The remote host is missing an update for the
# SPDX-FileCopyrightText: 2021 Greenbone AG
# Some text descriptions might be excerpted from (a) referenced
# source(s), and are Copyright (C) by the respective right holder(s).
#
# SPDX-License-Identifier: GPL-2.0-only
if(description)
{
script_oid("1.3.6.1.4.1.25623.1.0.844956");
script_cve_id("CVE-2021-25217");
script_tag(name:"creation_date", value:"2021-05-28 03:00:19 +0000 (Fri, 28 May 2021)");
script_version("2024-02-02T05:06:08+0000");
script_tag(name:"last_modification", value:"2024-02-02 05:06:08 +0000 (Fri, 02 Feb 2024)");
script_tag(name:"cvss_base", value:"3.3");
script_tag(name:"cvss_base_vector", value:"AV:A/AC:L/Au:N/C:N/I:N/A:P");
script_tag(name:"severity_vector", value:"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H");
script_tag(name:"severity_origin", value:"NVD");
script_tag(name:"severity_date", value:"2021-06-09 16:47:32 +0000 (Wed, 09 Jun 2021)");
script_name("Ubuntu: Security Advisory (USN-4969-1)");
script_category(ACT_GATHER_INFO);
script_copyright("Copyright (C) 2021 Greenbone AG");
script_family("Ubuntu Local Security Checks");
script_dependencies("gather-package-list.nasl");
script_mandatory_keys("ssh/login/ubuntu_linux", "ssh/login/packages", re:"ssh/login/release=UBUNTU(18\.04\ LTS|20\.04\ LTS|20\.10|21\.04)");
script_xref(name:"Advisory-ID", value:"USN-4969-1");
script_xref(name:"URL", value:"https://ubuntu.com/security/notices/USN-4969-1");
script_tag(name:"summary", value:"The remote host is missing an update for the 'isc-dhcp' package(s) announced via the USN-4969-1 advisory.");
script_tag(name:"vuldetect", value:"Checks if a vulnerable package version is present on the target host.");
script_tag(name:"insight", value:"Jon Franklin and Pawel Wieczorkiewicz discovered that DHCP incorrectly
handled lease file parsing. A remote attacker could possibly use this issue
to cause DHCP to crash, resulting in a denial of service.");
script_tag(name:"affected", value:"'isc-dhcp' package(s) on Ubuntu 18.04, Ubuntu 20.04, Ubuntu 20.10, Ubuntu 21.04.");
script_tag(name:"solution", value:"Please install the updated package(s).");
script_tag(name:"solution_type", value:"VendorFix");
script_tag(name:"qod_type", value:"package");
exit(0);
}
include("revisions-lib.inc");
include("pkg-lib-deb.inc");
release = dpkg_get_ssh_release();
if(!release)
exit(0);
res = "";
report = "";
if(release == "UBUNTU18.04 LTS") {
if(!isnull(res = isdpkgvuln(pkg:"isc-dhcp-client", ver:"4.3.5-3ubuntu7.3", rls:"UBUNTU18.04 LTS"))) {
report += res;
}
if(!isnull(res = isdpkgvuln(pkg:"isc-dhcp-server", ver:"4.3.5-3ubuntu7.3", rls:"UBUNTU18.04 LTS"))) {
report += res;
}
if(report != "") {
security_message(data:report);
} else if(__pkg_match) {
exit(99);
}
exit(0);
}
if(release == "UBUNTU20.04 LTS") {
if(!isnull(res = isdpkgvuln(pkg:"isc-dhcp-client", ver:"4.4.1-2.1ubuntu5.20.04.2", rls:"UBUNTU20.04 LTS"))) {
report += res;
}
if(!isnull(res = isdpkgvuln(pkg:"isc-dhcp-server", ver:"4.4.1-2.1ubuntu5.20.04.2", rls:"UBUNTU20.04 LTS"))) {
report += res;
}
if(report != "") {
security_message(data:report);
} else if(__pkg_match) {
exit(99);
}
exit(0);
}
if(release == "UBUNTU20.10") {
if(!isnull(res = isdpkgvuln(pkg:"isc-dhcp-client", ver:"4.4.1-2.1ubuntu10.1", rls:"UBUNTU20.10"))) {
report += res;
}
if(!isnull(res = isdpkgvuln(pkg:"isc-dhcp-server", ver:"4.4.1-2.1ubuntu10.1", rls:"UBUNTU20.10"))) {
report += res;
}
if(report != "") {
security_message(data:report);
} else if(__pkg_match) {
exit(99);
}
exit(0);
}
if(release == "UBUNTU21.04") {
if(!isnull(res = isdpkgvuln(pkg:"isc-dhcp-client", ver:"4.4.1-2.2ubuntu6.1", rls:"UBUNTU21.04"))) {
report += res;
}
if(!isnull(res = isdpkgvuln(pkg:"isc-dhcp-server", ver:"4.4.1-2.2ubuntu6.1", rls:"UBUNTU21.04"))) {
report += res;
}
if(report != "") {
security_message(data:report);
} else if(__pkg_match) {
exit(99);
}
exit(0);
}
exit(0);
CVSS2
Attack Vector
ADJACENT_NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:A/AC:L/Au:N/C:N/I:N/A:P
CVSS3
Attack Vector
ADJACENT
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
AI Score
Confidence
High
EPSS
Percentile
68.3%