Description
ISC DHCP 4.1.2 through 4.2.4 and 4.1-ESV before 4.1-ESV-R6 allows remote attackers to cause a denial of service (infinite loop and CPU consumption) via a malformed client identifier.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 13 | isc-dhcp | 4.2.4-2 | — |
| Debian 12 | isc-dhcp | 4.2.4-2 | — |
| Debian 6.0 | isc-dhcp | 4.1.1-P1-15+squeeze4 | DSA-2519-2, DSA-2519-1, DSA-2516-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 6 | dhcp +3 | 12:4.1.1-31.P1.el6_3.1 | RHSA-2012:1141 |
| RHEL 5 | dhcp +4 | 12:3.0.5-31.el5_8.1 | RHSA-2012:1140 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | dhcp | 4.3.3.P1-3.1 | openSUSE-SU-2024:10358-1 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.
Exploit-DB 1
- ISC DHCP 4.x - Multiple Denial of Service Vulnerabilities EDB-37538 · dos · Jul 25, 2012 · verified
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 6
- RHSA-2012:1140 Red Hat Security Advisory: dhcp security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- RHSA-2012:1141 Red Hat Security Advisory: dhcp security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- DSA-2519-1 isc-dhcp - denial of service Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-2519-2 isc-dhcp - denial of service Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-2516-1 isc-dhcp - denial of service Debian Security (DSA / DLA) · Mar 9, 2026
- openSUSE-SU-2024:10358-1 dhcp-4.3.3.P1-3.1 on GA media SUSE / openSUSE Security Updates · May 7, 2025
References
- http://www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.html
- https://kb.isc.org/article/AA-00712
- DSA-2516 vendor-advisory
- RHSA-2012:1141 vendor-advisory
- MDVSA-2012:116 vendor-advisory
- openSUSE-SU-2012:1006 vendor-advisory
- http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10761
- MDVSA-2012:115 vendor-advisory
- DSA-2519 vendor-advisory
- USN-1519-1 vendor-advisory
- GLSA-201301-06 vendor-advisory
- RHSA-2012:1140 vendor-advisory
- 54665 vdb-entry