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 consu
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.
- Published
- Jul 25, 2012
- Updated
- Jun 16, 2026
- EPSS
- 13.0% · 96th percentile
- CWE
- CWE-119
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Report tools
Action score
28
Monitor
Low priority for now.
- CVSS
- 24 / 40 · 6.1 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 4 / 30 · 13.0%
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| isc | dhcp | cpe:2.3:a:isc:dhcp |
| canonical | ubuntu linux | cpe:2.3:o:canonical:ubuntu_linux |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- canonical ubuntu linux11.04
- canonical ubuntu linux11.10
- canonical ubuntu linux12.04
- debian debian linux6.0
- debian debian linux7.0
- isc dhcp4.1-esv
- isc dhcp4.1.2
- isc dhcp4.2.0
- isc dhcp4.2.1
- isc dhcp4.2.2
- isc dhcp4.2.3
- isc dhcp4.2.4
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | isc-dhcp | before 4.2.4-2 | 4.2.4-2 |
| Debian:6.0 | isc-dhcp | before 4.1.1-P1-15+squeeze4 | 4.1.1-P1-15+squeeze4 |
| Debian:6.0 | isc-dhcp | before 4.1.1-P1-15+squeeze5 | 4.1.1-P1-15+squeeze5 |
| Debian:6.0 | isc-dhcp | before 4.1.1-P1-15+squeeze6 | 4.1.1-P1-15+squeeze6 |
| openSUSE:Tumbleweed | dhcp | before 4.3.3.P1-3.1 | 4.3.3.P1-3.1 |
| Red Hat:enterprise_linux:5::client | dhclient | before 12:3.0.5-31.el5_8.1 | 12:3.0.5-31.el5_8.1 |
| Red Hat:enterprise_linux:5::client | dhcp | before 12:3.0.5-31.el5_8.1 | 12:3.0.5-31.el5_8.1 |
| Red Hat:enterprise_linux:5::client | dhcp-debuginfo | before 12:3.0.5-31.el5_8.1 | 12:3.0.5-31.el5_8.1 |
| Red Hat:enterprise_linux:5::client | libdhcp4client | before 12:3.0.5-31.el5_8.1 | 12:3.0.5-31.el5_8.1 |
| Red Hat:enterprise_linux:5::client_workstation | dhcp-devel | before 12:3.0.5-31.el5_8.1 | 12:3.0.5-31.el5_8.1 |
| Red Hat:enterprise_linux:5::client_workstation | libdhcp4client-devel | before 12:3.0.5-31.el5_8.1 | 12:3.0.5-31.el5_8.1 |
| Red Hat:enterprise_linux:6::client | dhclient | before 12:4.1.1-31.P1.el6_3.1 | 12:4.1.1-31.P1.el6_3.1 |
| Red Hat:enterprise_linux:6::client | dhcp | before 12:4.1.1-31.P1.el6_3.1 | 12:4.1.1-31.P1.el6_3.1 |
| Red Hat:enterprise_linux:6::client | dhcp-common | before 12:4.1.1-31.P1.el6_3.1 | 12:4.1.1-31.P1.el6_3.1 |
| Red Hat:enterprise_linux:6::client | dhcp-debuginfo | before 12:4.1.1-31.P1.el6_3.1 | 12:4.1.1-31.P1.el6_3.1 |
| Red Hat:enterprise_linux:6::client | dhcp-devel | before 12:4.1.1-31.P1.el6_3.1 | 12:4.1.1-31.P1.el6_3.1 |
Same product
isc: all recordsOther highest-scoring records for the same primary product.
- CVE-2011-0997dhclient in ISC DHCP 3.0.x through 4.2.x before 4.2.1-P1, 3.1-ESV before 3.1-ESV-R1, and 4.1-ESV before 4.1-ESV-R2 allows remote attackers t55Plan
- CVE-2017-3144Failure to properly clean up closed OMAPI connections can exhaust available sockets52Plan
- CVE-2015-8605ISC DHCP 4.x before 4.1-ESV-R12-P1, 4.2.x, and 4.3.x before 4.3.3-P1 allows remote attackers to cause a denial of service (application crash51Plan
- CVE-2009-0692Stack-based buffer overflow in the script_write_params method in client/dhclient.c in ISC DHCP dhclient 4.1 before 4.1.0p1, 4.0 before 4.0.148Plan
- CVE-2016-2774ISC 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 number of concurrent TCP sessions, which allows rem45Plan
- CVE-2011-2749The server in ISC DHCP 3.x and 4.x before 4.2.2, 3.1-ESV before 3.1-ESV-R3, and 4.1-ESV before 4.1-ESV-R3 allows remote attackers to cause a43Plan
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| debian:isc-dhcp | 4.2.4-2 · Debian:12 | Package registry (OSV) |
| opensuse:dhcp | 4.3.3.P1-3.1 · openSUSE:Tumbleweed | Package registry (OSV) |
| red hat:dhclient | 12:3.0.5-31.el5_8.1 · Red Hat:enterprise_linux:5::client | Package registry (OSV) |
| red hat:dhcp | 12:3.0.5-31.el5_8.1 · Red Hat:enterprise_linux:5::client | Package registry (OSV) |
| red hat:dhcp-common | 12:4.1.1-31.P1.el6_3.1 · Red Hat:enterprise_linux:6::client | Package registry (OSV) |
| red hat:dhcp-debuginfo | 12:3.0.5-31.el5_8.1 · Red Hat:enterprise_linux:5::client | Package registry (OSV) |
| red hat:dhcp-devel | 12:3.0.5-31.el5_8.1 · Red Hat:enterprise_linux:5::client_workstation | Package registry (OSV) |
| red hat:libdhcp4client | 12:3.0.5-31.el5_8.1 · Red Hat:enterprise_linux:5::client | Package registry (OSV) |
| red hat:libdhcp4client-devel | 12:3.0.5-31.el5_8.1 · Red Hat:enterprise_linux:5::client_workstation | Package registry (OSV) |
Exploit status
Proof of concept available
A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.
Evidence
- Exploit-DB entry ×1
Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.
| Source | Kind | Date |
|---|---|---|
| Exploit-DB entry | dos | 2012-07-25 |
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
- First PoCsame day
- Published
- TodaySep 30, 2026+5180 d
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- C · the service can be disrupted
- Attack complexity
- Low
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- C
Weakness class (CWE)
CWE-119 · Improper Restriction of Operations within the Bounds of a Memory BufferCVSS vector
AV:A/AC:L/Au:N/C:N/I:N/A:C
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
- Buffer Overflow via Environment VariablesCAPEC-10likelihood: High · High
- Overflow BuffersCAPEC-100likelihood: High · Very High
- Buffer ManipulationCAPEC-123likelihood: High · Very High
- Client-side Injection-induced Buffer OverflowCAPEC-14likelihood: Medium · High
- Filter Failure through Buffer OverflowCAPEC-24likelihood: High · High
- MIME ConversionCAPEC-42likelihood: High · High
- Overflow Binary Resource FileCAPEC-44likelihood: High · Very High
- Buffer Overflow via Symbolic LinksCAPEC-45likelihood: High · High
ATT&CK techniques
—
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpChange log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- kb.juniper.net/InfoCenter/index?page=content&id=JSA10761
- lists.opensuse.org/opensuse-updates/2012-08/msg00030.html
- rhn.redhat.com/errata/RHSA-2012-1140.html
- rhn.redhat.com/errata/RHSA-2012-1141.html
- security.gentoo.org/glsa/glsa-201301-06.xml
- www.debian.org/security/2012/dsa-2516
- www.debian.org/security/2012/dsa-2519
- www.mandriva.com/security/advisories?name=MDVSA-2012:115
- www.mandriva.com/security/advisories?name=MDVSA-2012:116
- www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.html
- www.securityfocus.com/bid/54665
- www.ubuntu.com/usn/USN-1519-1
- kb.isc.org/article/AA-00712
Vendor advisories and official records. Exploit/PoC links are deliberately left out.