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NVD / CVE Program· CNA mitre

CVE-2012-3571: 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…

MediumCVSS 6.1 · v2.0—Proof of concept Fix available

Noroxi assessment

Priority: Monitor (action score 28/100)

  • Public proof-of-concept code exists (Exploit-DB); there is no record of exploitation in the wild.
  • Probability of exploitation in the next 30 days: 12.9% (FIRST EPSS); higher than 96.3% of all records.
  • No special conditions are required; it is repeatable.
  • Fixed version: isc-dhcp (Debian:12) 4.2.4-2; isc-dhcp (Debian:6.0) 4.1.1-P1-15+squeeze6, 4.1.1-P1-15+squeeze4, 4.1.1-P1-15+squeeze5; dhcp (openSUSE:Tumbleweed) 4.3.3.P1-3.1.

Low priority for now. Upgrade to isc-dhcp (Debian:12) 4.2.4-2; isc-dhcp (Debian:6.0) 4.1.1-P1-15+squeeze6, 4.1.1-P1-15+squeeze4, 4.1.1-P1-15+squeeze5; dhcp (openSUSE:Tumbleweed) 4.3.3.P1-3.1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

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
12.9% · 96th percentile

Report tools

JSON

Action score

28

Monitor

Low priority for now.

CVSS
24 / 40 · 6.1 / 10
CISA KEV
0 / 30 · Not listed
EPSS
4 / 30 · 12.9%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • Proof of concept exists, no weaponized module
  • A fix has been released

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  • when exploit code appears or is weaponized
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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
iscdhcp
canonicalubuntu linux
debiandebian 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
+4 more rows
  • 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.

EcosystemPackageAffected rangeFix
Debian:12isc-dhcpbefore 4.2.4-24.2.4-2
Debian:6.0isc-dhcpbefore 4.1.1-P1-15+squeeze64.1.1-P1-15+squeeze6
Debian:6.0isc-dhcpbefore 4.1.1-P1-15+squeeze44.1.1-P1-15+squeeze4
Debian:6.0isc-dhcpbefore 4.1.1-P1-15+squeeze54.1.1-P1-15+squeeze5
openSUSE:Tumbleweeddhcpbefore 4.3.3.P1-3.14.3.3.P1-3.1
Red Hat:enterprise_linux:5::clientdhclientbefore 12:3.0.5-31.el5_8.112:3.0.5-31.el5_8.1
Red Hat:enterprise_linux:5::clientdhcpbefore 12:3.0.5-31.el5_8.112:3.0.5-31.el5_8.1
Red Hat:enterprise_linux:5::clientdhcp-debuginfobefore 12:3.0.5-31.el5_8.112:3.0.5-31.el5_8.1
Red Hat:enterprise_linux:5::clientlibdhcp4clientbefore 12:3.0.5-31.el5_8.112:3.0.5-31.el5_8.1
Red Hat:enterprise_linux:5::client_workstationdhcp-develbefore 12:3.0.5-31.el5_8.112:3.0.5-31.el5_8.1
Red Hat:enterprise_linux:5::client_workstationlibdhcp4client-develbefore 12:3.0.5-31.el5_8.112:3.0.5-31.el5_8.1
Red Hat:enterprise_linux:6::clientdhclientbefore 12:4.1.1-31.P1.el6_3.112:4.1.1-31.P1.el6_3.1
Red Hat:enterprise_linux:6::clientdhcpbefore 12:4.1.1-31.P1.el6_3.112:4.1.1-31.P1.el6_3.1
Red Hat:enterprise_linux:6::clientdhcp-commonbefore 12:4.1.1-31.P1.el6_3.112:4.1.1-31.P1.el6_3.1
Red Hat:enterprise_linux:6::clientdhcp-debuginfobefore 12:4.1.1-31.P1.el6_3.112:4.1.1-31.P1.el6_3.1
Red Hat:enterprise_linux:6::clientdhcp-develbefore 12:4.1.1-31.P1.el6_3.112:4.1.1-31.P1.el6_3.1

Same product

isc: all records

Other 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…
    55Plan
  • CVE-2017-3144Failure to properly clean up closed OMAPI connections can exhaust available sockets
    52Plan
  • 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…
    51Plan

Published before and after this one in the same product

  • ← EarlierCVE-2011-4868Jan 14, 2012 · The logging functionality in dhcpd in ISC DHCP before 4.2.3-P2, when using Dynamic DNS (DDNS) and issuing IPv6 addresses, does not properly…
    25Monitor
  • ← EarlierCVE-2012-3570Jul 25, 2012 · Buffer overflow in ISC DHCP 4.2.x before 4.2.4-P1, when DHCPv6 mode is enabled, allows remote attackers to cause a denial of service…
    23Monitor
  • Later →CVE-2012-3954Jul 25, 2012 · Multiple memory leaks in ISC DHCP 4.1.x and 4.2.x before 4.2.4-P1 and 4.1-ESV before 4.1-ESV-R6 allow remote attackers to cause a denial of…
    14Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
debian:isc-dhcp4.2.4-2 · Debian:12Package registry (OSV)
opensuse:dhcp4.3.3.P1-3.1 · openSUSE:TumbleweedPackage registry (OSV)
red hat:dhclient12:3.0.5-31.el5_8.1 · Red Hat:enterprise_linux:5::clientPackage registry (OSV)
red hat:dhcp12:3.0.5-31.el5_8.1 · Red Hat:enterprise_linux:5::clientPackage registry (OSV)
red hat:dhcp-common12:4.1.1-31.P1.el6_3.1 · Red Hat:enterprise_linux:6::clientPackage registry (OSV)
red hat:dhcp-debuginfo12:3.0.5-31.el5_8.1 · Red Hat:enterprise_linux:5::clientPackage registry (OSV)
red hat:dhcp-devel12:3.0.5-31.el5_8.1 · Red Hat:enterprise_linux:5::client_workstationPackage registry (OSV)
red hat:libdhcp4client12:3.0.5-31.el5_8.1 · Red Hat:enterprise_linux:5::clientPackage registry (OSV)
red hat:libdhcp4client-devel12:3.0.5-31.el5_8.1 · Red Hat:enterprise_linux:5::client_workstationPackage 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.

Public exploit evidence
SourceKindDate
Exploit-DB entrydos2012-07-25

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.

  1. First PoCsame day
  2. Published
  3. TodayNov 15, 2026+5226 d

Not on record for this CVE: EPSS history · patch commit or PR link · researcher credit · variant or chain candidate · public bounty program.

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 Buffer

CVSS 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.

ATT&CK techniques

—

References

Show all references (12 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records