ISC DHCP up to 4.4.0 Reference Counter Packet integer overflow

CVSS Meta Temp Score
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CTI Interest Score
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5.8$0-$5k0.00

Summaryinfo

A vulnerability was found in ISC DHCP. It has been rated as problematic. This issue affects some unknown processing of the component Reference Counter. The manipulation as part of Packet leads to integer overflow. This vulnerability is referenced as CVE-2018-5733. The attack needs to be initiated within the local network. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in ISC DHCP (Network Management Software). It has been rated as problematic. This issue affects an unknown function of the component Reference Counter. The manipulation as part of a Packet leads to a integer overflow vulnerability. Using CWE to declare the problem leads to CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. Impacted is availability. The summary by CVE is:

A malicious client which is allowed to send very large amounts of traffic (billions of packets) to a DHCP server can eventually overflow a 32-bit reference counter, potentially causing dhcpd to crash. Affects ISC DHCP 4.1.0 -> 4.1-ESV-R15, 4.2.0 -> 4.2.8, 4.3.0 -> 4.3.6, 4.4.0.

The bug was discovered 02/28/2018. The weakness was published 01/16/2019 by Felix Wilhelm with Google Security Team (Website). It is possible to read the advisory at kb.isc.org. The identification of this vulnerability is CVE-2018-5733 since 01/17/2018. The attack needs to approached within the local network. No form of authentication is needed for a successful exploitation. The technical details are unknown and an exploit is not publicly available.

The vulnerability was handled as a non-public zero-day exploit for at least 36 days. During that time the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 108847 (Amazon Linux AMI : dhcp (ALAS-2018-984)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Amazon Linux Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 236673 (Red Hat Update for dhcp (RHSA-2018:0483)).

Upgrading eliminates this vulnerability. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (108847) and SecurityFocus (BID 103188†). Similar entry is available at VDB-143197. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.9
VulDB Meta Temp Score: 5.8

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CNA Base Score: 5.9
CNA Vector (Internet Systems Consortium (ISC)): 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Integer overflow
CWE: CWE-190 / CWE-189
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 108847
Nessus Name: Amazon Linux AMI : dhcp (ALAS-2018-984)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 900031
OpenVAS Name: Debian LTS Advisory ([SECURITY] [DLA 1313-1] isc-dhcp security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

01/17/2018 🔍
02/28/2018 +42 days 🔍
02/28/2018 +0 days 🔍
04/05/2018 +36 days 🔍
04/06/2018 +1 days 🔍
01/16/2019 +285 days 🔍
01/16/2019 +0 days 🔍
01/17/2019 +1 days 🔍
04/26/2025 +2291 days 🔍

Sourcesinfo

Vendor: isc.org

Advisory: RHSA-2018:0469
Researcher: Felix Wilhelm
Organization: Google Security Team
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2018-5733 (🔍)
GCVE (CVE): GCVE-0-2018-5733
GCVE (VulDB): GCVE-100-129815

OVAL: 🔍

SecurityFocus: 103188 - ISC DHCP CVE-2018-5733 Remote Denial of Service Vulnerability
SecurityTracker: 1040437

See also: 🔍

Entryinfo

Created: 01/17/2019 11:46
Updated: 04/26/2025 03:06
Changes: 01/17/2019 11:46 (77), 05/02/2020 09:27 (6), 07/01/2023 12:13 (5), 07/01/2023 12:20 (10), 04/26/2025 03:06 (16)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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