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TI-2018-04139 Aliases CVE-2018-5732GHSA-j4cm-vph7-f7qg

A specially constructed response from a malicious server can cause a buffer overflow in dhclient

Priority MEDIUM 41CWE-119Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 18 fixed, 1 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-119 and the CVSS impact.

Summary

Failure to properly bounds-check a buffer used for processing DHCP options allows a malicious server (or an entity masquerading as a server) to cause a buffer overflow (and resulting crash) in dhclient by sending a response containing a specially constructed options section. Affects ISC DHCP versions 4.1.0 -> 4.1-ESV-R15, 4.2.0 -> 4.2.8, 4.3.0 -> 4.3.6, 4.4.0

Why it matters now

EPSS 0.05244 92nd percentileScored 2026-11-07
Fix Partial Red Hat: 2 advisoriesRed Hat: 18 fixed, 1 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
ISCISC DHCPISC DHCP 4.1.0 -> 4.1-ESV-R15, 4.2.0 -> 4.2.8, 4.3.0 -> 4.3.6, 4.4.0—No fix listedCNA
  • ISC DHCP VendorISC Affected ISC DHCP 4.1.0 -> 4.1-ESV-R15, 4.2.0 -> 4.2.8, 4.3.0 -> 4.3.6, 4.4.0 Fixed in — No fix listed CNA

CPE configurations NVD · 36

CPEVersionsRoleVendor
cpe:2.3:a:isc:dhcp:*:*:*:*:*:*:*:*4.1.0 – 4.1.2; 4.2.0 to before 4.2.8; 4.3.0 to before 4.3.6VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:-:*:*:*:*:*:*4.1-esvVulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r1:*:*:*:*:*:*4.1-esv r1VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r10:*:*:*:*:*:*4.1-esv r10VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r10b1:*:*:*:*:*:*4.1-esv r10b1VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r10rc1:*:*:*:*:*:*4.1-esv r10rc1VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r11:*:*:*:*:*:*4.1-esv r11VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r11b1:*:*:*:*:*:*4.1-esv r11b1VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r11rc1:*:*:*:*:*:*4.1-esv r11rc1VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r11rc2:*:*:*:*:*:*4.1-esv r11rc2VulnerableISC
  • cpe:2.3:a:isc:dhcp:*:*:*:*:*:*:*:* Versions 4.1.0 – 4.1.2; 4.2.0 to before 4.2.8; 4.3.0 to before 4.3.6 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:-:*:*:*:*:*:* Versions 4.1-esv Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r1:*:*:*:*:*:* Versions 4.1-esv r1 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r10:*:*:*:*:*:* Versions 4.1-esv r10 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r10b1:*:*:*:*:*:* Versions 4.1-esv r10b1 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r10rc1:*:*:*:*:*:* Versions 4.1-esv r10rc1 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r11:*:*:*:*:*:* Versions 4.1-esv r11 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r11b1:*:*:*:*:*:* Versions 4.1-esv r11b1 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r11rc1:*:*:*:*:*:* Versions 4.1-esv r11rc1 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r11rc2:*:*:*:*:*:* Versions 4.1-esv r11rc2 Vulnerable ·ISC
Show 26 more CPE
CPEVersionsRoleVendor
cpe:2.3:a:isc:dhcp:4.1-esv:r12:*:*:*:*:*:*4.1-esv r12VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r12-p1:*:*:*:*:*:*4.1-esv r12-p1VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r12b1:*:*:*:*:*:*4.1-esv r12b1VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r13:*:*:*:*:*:*4.1-esv r13VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r13b1:*:*:*:*:*:*4.1-esv r13b1VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r14:*:*:*:*:*:*4.1-esv r14VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r14b1:*:*:*:*:*:*4.1-esv r14b1VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r15:*:*:*:*:*:*4.1-esv r15VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r2:*:*:*:*:*:*4.1-esv r2VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r3:*:*:*:*:*:*4.1-esv r3VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r3b1:*:*:*:*:*:*4.1-esv r3b1VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r4:*:*:*:*:*:*4.1-esv r4VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r5:*:*:*:*:*:*4.1-esv r5VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r5b1:*:*:*:*:*:*4.1-esv r5b1VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r5rc1:*:*:*:*:*:*4.1-esv r5rc1VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r5rc2:*:*:*:*:*:*4.1-esv r5rc2VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r6:*:*:*:*:*:*4.1-esv r6VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r7:*:*:*:*:*:*4.1-esv r7VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r8:*:*:*:*:*:*4.1-esv r8VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r8b1:*:*:*:*:*:*4.1-esv r8b1VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r8rc1:*:*:*:*:*:*4.1-esv r8rc1VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r9:*:*:*:*:*:*4.1-esv r9VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r9b1:*:*:*:*:*:*4.1-esv r9b1VulnerableISC
cpe:2.3:a:isc:dhcp:4.1-esv:r9rc1:*:*:*:*:*:*4.1-esv r9rc1VulnerableISC
cpe:2.3:a:isc:dhcp:4.1.2:p1:*:*:*:*:*:*4.1.2 p1VulnerableISC
cpe:2.3:a:isc:dhcp:4.4.0:*:*:*:*:*:*:*4.4.0VulnerableISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r12:*:*:*:*:*:* Versions 4.1-esv r12 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r12-p1:*:*:*:*:*:* Versions 4.1-esv r12-p1 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r12b1:*:*:*:*:*:* Versions 4.1-esv r12b1 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r13:*:*:*:*:*:* Versions 4.1-esv r13 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r13b1:*:*:*:*:*:* Versions 4.1-esv r13b1 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r14:*:*:*:*:*:* Versions 4.1-esv r14 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r14b1:*:*:*:*:*:* Versions 4.1-esv r14b1 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r15:*:*:*:*:*:* Versions 4.1-esv r15 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r2:*:*:*:*:*:* Versions 4.1-esv r2 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r3:*:*:*:*:*:* Versions 4.1-esv r3 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r3b1:*:*:*:*:*:* Versions 4.1-esv r3b1 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r4:*:*:*:*:*:* Versions 4.1-esv r4 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r5:*:*:*:*:*:* Versions 4.1-esv r5 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r5b1:*:*:*:*:*:* Versions 4.1-esv r5b1 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r5rc1:*:*:*:*:*:* Versions 4.1-esv r5rc1 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r5rc2:*:*:*:*:*:* Versions 4.1-esv r5rc2 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r6:*:*:*:*:*:* Versions 4.1-esv r6 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r7:*:*:*:*:*:* Versions 4.1-esv r7 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r8:*:*:*:*:*:* Versions 4.1-esv r8 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r8b1:*:*:*:*:*:* Versions 4.1-esv r8b1 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r8rc1:*:*:*:*:*:* Versions 4.1-esv r8rc1 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r9:*:*:*:*:*:* Versions 4.1-esv r9 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r9b1:*:*:*:*:*:* Versions 4.1-esv r9b1 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1-esv:r9rc1:*:*:*:*:*:* Versions 4.1-esv r9rc1 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.1.2:p1:*:*:*:*:*:* Versions 4.1.2 p1 Vulnerable ·ISC
  • cpe:2.3:a:isc:dhcp:4.4.0:*:*:*:*:*:*:* Versions 4.4.0 Vulnerable ·ISC

Remediation

Red Hat 2 advisories

  • RHSA-2018:0483 Released 2018-03-12 · Red Hat rating Important
    dhcp security update
    • Red Hat Enterprise Linux Client (v. 7) dhclient-12:4.2.5-58.el7_4.3, dhcp-12:4.2.5-58.el7_4.3, dhcp-common-12:4.2.5-58.el7_4.3 +1
    • Red Hat Enterprise Linux Client Optional (v. 7) dhcp-12:4.2.5-58.el7_4.3, dhcp-devel-12:4.2.5-58.el7_4.3
    • Red Hat Enterprise Linux ComputeNode (v. 7) dhclient-12:4.2.5-58.el7_4.3, dhcp-12:4.2.5-58.el7_4.3, dhcp-common-12:4.2.5-58.el7_4.3 +1
    • Red Hat Enterprise Linux ComputeNode Optional (v. 7) dhcp-12:4.2.5-58.el7_4.3, dhcp-devel-12:4.2.5-58.el7_4.3
    • Red Hat Enterprise Linux Server (v. 7) dhclient-12:4.2.5-58.el7_4.3, dhcp-12:4.2.5-58.el7_4.3, dhcp-common-12:4.2.5-58.el7_4.3 +2
    • Red Hat Enterprise Linux Server Optional (v. 7) dhcp-devel-12:4.2.5-58.el7_4.3, dhcp-devel-12:4.2.5-58.el7_4.3.ppc
    • Red Hat Enterprise Linux Workstation (v. 7) dhclient-12:4.2.5-58.el7_4.3, dhcp-12:4.2.5-58.el7_4.3, dhcp-common-12:4.2.5-58.el7_4.3 +1
    • Red Hat Enterprise Linux Workstation Optional (v. 7) dhcp-devel-12:4.2.5-58.el7_4.3
    • Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7) dhclient-12:4.2.5-58.el7_4.3, dhcp-12:4.2.5-58.el7_4.3, dhcp-common-12:4.2.5-58.el7_4.3 +1
    • Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7) dhcp-devel-12:4.2.5-58.el7_4.3
  • RHSA-2018:0469 Released 2018-03-09 · Red Hat rating Important
    dhcp security update
    • Red Hat Enterprise Linux Desktop (v. 6) dhclient-12:4.1.1-53.P1.el6_9.3, dhcp-12:4.1.1-53.P1.el6_9.3, dhcp-common-12:4.1.1-53.P1.el6_9.3
    • Red Hat Enterprise Linux Desktop Optional (v. 6) dhcp-12:4.1.1-53.P1.el6_9.3, dhcp-devel-12:4.1.1-53.P1.el6_9.3
    • Red Hat Enterprise Linux HPC Node (v. 6) dhclient-12:4.1.1-53.P1.el6_9.3, dhcp-12:4.1.1-53.P1.el6_9.3, dhcp-common-12:4.1.1-53.P1.el6_9.3
    • Red Hat Enterprise Linux HPC Node Optional (v. 6) dhcp-12:4.1.1-53.P1.el6_9.3, dhcp-devel-12:4.1.1-53.P1.el6_9.3
    • Red Hat Enterprise Linux Server (v. 6) dhclient-12:4.1.1-53.P1.el6_9.3, dhcp-12:4.1.1-53.P1.el6_9.3, dhcp-common-12:4.1.1-53.P1.el6_9.3
    • Red Hat Enterprise Linux Server Optional (v. 6) dhcp-devel-12:4.1.1-53.P1.el6_9.3, dhcp-devel-12:4.1.1-53.P1.el6_9.3.ppc
    • Red Hat Enterprise Linux Workstation (v. 6) dhclient-12:4.1.1-53.P1.el6_9.3, dhcp-12:4.1.1-53.P1.el6_9.3, dhcp-common-12:4.1.1-53.P1.el6_9.3
    • Red Hat Enterprise Linux Workstation Optional (v. 6) dhcp-devel-12:4.1.1-53.P1.el6_9.3

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 5AffectedNo fix planned: Will not fix
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2018:0483
Red Hat Enterprise Linux Client Optional (v. 7)Fixed RHSA-2018:0483
Red Hat Enterprise Linux ComputeNode (v. 7)Fixed RHSA-2018:0483
Red Hat Enterprise Linux ComputeNode Optional (v. 7)Fixed RHSA-2018:0483
Red Hat Enterprise Linux Desktop (v. 6)Fixed RHSA-2018:0469
Red Hat Enterprise Linux Desktop Optional (v. 6)Fixed RHSA-2018:0469
Red Hat Enterprise Linux HPC Node (v. 6)Fixed RHSA-2018:0469
Red Hat Enterprise Linux HPC Node Optional (v. 6)Fixed RHSA-2018:0469
Red Hat Enterprise Linux Server (v. 6)Fixed RHSA-2018:0469
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2018:0483
Red Hat Enterprise Linux Server Optional (v. 6)Fixed RHSA-2018:0469
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2018:0483
Red Hat Enterprise Linux Workstation (v. 6)Fixed RHSA-2018:0469
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2018:0483
Red Hat Enterprise Linux Workstation Optional (v. 6)Fixed RHSA-2018:0469
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2018:0483
Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7)Fixed RHSA-2018:0483
Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7)Fixed RHSA-2018:0483
Not affected: 1 product
  • Red Hat Enterprise Linux 8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2018-5732
  2. 2026-10-03 Alias added: GHSA-j4cm-vph7-f7qg

References

Advisory 1

  • TI-2011-00858 dhclient in ISC DHCP 3.0.x through 4.2.x before 4.2.1-P1, 3.1-ESV before 3.1-ESV-R1, and… CVSS 2.0HIGH 7.5
  • TI-2017-02364 Failure to properly clean up closed OMAPI connections can exhaust available sockets CVSS 3.1HIGH 7.5
  • TI-2015-07072 ISC DHCP 4.x before 4.1-ESV-R12-P1, 4.2.x, and 4.3.x before 4.3.3-P1 allows remote… CVSS 3.0MEDIUM 6.5
  • TI-2016-02318 ISC DHCP 4.1.x before 4.1-ESV-R13 and 4.2.x and 4.3.x before 4.3.4 does not restrict the… CVSS 3.1MEDIUM 5.9
  • TI-2009-00661 Stack-based buffer overflow in the script_write_params method in client/dhclient.c in ISC… CVSS 2.0HIGH 10.0
  • TI-2010-02068 ISC DHCP 4.1 before 4.1.1-P1 and 4.0 before 4.0.2-P1 allows remote attackers to cause a… CVSS 2.0MEDIUM 5.0
See all 24 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences