CVE-2016-2774: Input Validation

Published Mar 9, 2016
·
Updated

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 number of concurrent TCP sessions, which allows remote attackers to cause a denial of service (INSIST assertion failure or request-processing outage) by establishing many sessions.

Affected Software

96 affected componentsFixes available
ISC DHCP=4.1-esv
ISC DHCP=4.1-esv-r1
ISC DHCP=4.1-esv-r10
ISC DHCP=4.1-esv-r10_b1
ISC DHCP=4.1-esv-r11_b1
ISC DHCP=4.1-esv-r11_rc1
ISC DHCP=4.1-esv-r11_rc2
ISC DHCP=4.1-esv-r12
ISC DHCP=4.1-esv-r12_b1
ISC DHCP=4.1-esv-r2
ISC DHCP=4.1-esv-r3
ISC DHCP=4.1-esv-r3_b1
ISC DHCP=4.1-esv-r4
ISC DHCP=4.1-esv-r5
ISC DHCP=4.1-esv-r5_b1
ISC DHCP=4.1-esv-r5_rc1
ISC DHCP=4.1-esv-r5_rc2
ISC DHCP=4.1-esv-r6
ISC DHCP=4.1-esv-r7
ISC DHCP=4.1-esv-r8
ISC DHCP=4.1-esv-r8_b1
ISC DHCP=4.1-esv-r8_rc1
ISC DHCP=4.1-esv-r9
ISC DHCP=4.1-esv-r9_b1
ISC DHCP=4.1-esv-r9_rc1
ISC DHCP=4.1-esv-rc1
ISC DHCP=4.1.0
ISC DHCP=4.1.0-a1
ISC DHCP=4.1.0-a2
ISC DHCP=4.1.0-b1
ISC DHCP=4.1.1
ISC DHCP=4.1.1-b1
ISC DHCP=4.1.1-b2
ISC DHCP=4.1.1-b3
ISC DHCP=4.1.1-p1
ISC DHCP=4.1.1-rc1
ISC DHCP=4.1.2
ISC DHCP=4.1.2-b1
ISC DHCP=4.1.2-p1
ISC DHCP=4.1.2-rc1
ISC DHCP=4.2.0
ISC DHCP=4.2.0-a1
ISC DHCP=4.2.0-a2
ISC DHCP=4.2.0-b1
ISC DHCP=4.2.0-b2
ISC DHCP=4.2.0-p1
ISC DHCP=4.2.0-p2
ISC DHCP=4.2.0-rc1
ISC DHCP=4.2.1
ISC DHCP=4.2.1-b1
ISC DHCP=4.2.1-p1
ISC DHCP=4.2.1-rc1
ISC DHCP=4.2.2
ISC DHCP=4.2.2-b1
ISC DHCP=4.2.2-rc1
ISC DHCP=4.2.3
ISC DHCP=4.2.3-p1
ISC DHCP=4.2.3-p2
ISC DHCP=4.2.4
ISC DHCP=4.2.4-b1
ISC DHCP=4.2.4-p1
ISC DHCP=4.2.4-p2
ISC DHCP=4.2.4-rc1
ISC DHCP=4.2.4-rc2
ISC DHCP=4.2.5
ISC DHCP=4.2.5-b1
ISC DHCP=4.2.5-p1
ISC DHCP=4.2.5-rc1
ISC DHCP=4.2.6
ISC DHCP=4.2.6-b1
ISC DHCP=4.2.6-rc1
ISC DHCP=4.2.7
ISC DHCP=4.2.7-b1
ISC DHCP=4.2.7-rc1
ISC DHCP=4.2.8
ISC DHCP=4.2.8-b1
ISC DHCP=4.2.8-rc1
ISC DHCP=4.2.8-rc2
ISC DHCP=4.3.0
ISC DHCP=4.3.0-a1
ISC DHCP=4.3.0-b1
ISC DHCP=4.3.0-rc1
ISC DHCP=4.3.1
ISC DHCP=4.3.1-b1
ISC DHCP=4.3.1-rc1
ISC DHCP=4.3.2
ISC DHCP=4.3.2-b1
ISC DHCP=4.3.2-rc1
ISC DHCP=4.3.2-rc2
ISC DHCP=4.3.3
ISC DHCP=4.3.3-b1
Debian Debian Linux=8.0
Canonical Ubuntu Linux=14.04
Canonical Ubuntu Linux=16.04
Canonical Ubuntu Linux=17.10
debian/isc-dhcp
4.4.1-2.3+deb11u24.4.1-2.3+deb11u14.4.3-P1-24.4.3-P1-8

Remediation

Patch Available

https://source.isc.org/cgi-bin/gitweb.cgi?p=dhcp.git;a=commit;h=0b209ea5cc333255e055113fa2ad636dda681a21

Event History

Mar 9, 2016
CVE Published
via MITRE·03:26 PM
Data Sourced
via MITRE·03:26 PM
Description
Data Sourced
via NVD·03:59 PM
DescriptionSeverityWeaknessAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·10:16 PM
Description
Feb 20, 2026
Data Sourced
via Ubuntu·04:51 PM
RemedyDescriptionSeverityAffected Software
Data Sourced
via Debian·04:51 PM
DescriptionAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2016-2774?

CVE-2016-2774 has a high severity rating as it allows remote attackers to cause a denial of service by overwhelming the DHCP server.

2

How do I fix CVE-2016-2774?

To fix CVE-2016-2774, upgrade to ISC DHCP versions 4.1-ESV-R13 or later, or 4.3.4 or later.

3

What versions are affected by CVE-2016-2774?

CVE-2016-2774 affects ISC DHCP versions 4.1.x before 4.1-ESV-R13 and 4.2.x and 4.3.x before 4.3.4.

4

What impact can CVE-2016-2774 have on my network?

CVE-2016-2774 can result in system crashes and request-processing outages, significantly disrupting network services.

5

Is there a workaround for CVE-2016-2774?

Currently, there are no known workarounds for CVE-2016-2774; upgrading to a secure version is the only mitigation.

Company

Resources

Contact

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