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Fencer Intel
high 7.5

CVE-2011-0997 in the critical feed json

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 4.1-ESV before 4.1-ESV-R2 allows remote attackers…

published 2011-04-08 15 y ago modified 2026-06-16 4 mo ago also EUVD-2011-1008

cvss
7.5
version 2.0, NVD
cisa kev
Not listed
not in CISA's catalog
epss
84.6%
EPSS 84.6% chance of exploitation in 30 days, percentile 99.7%
public exploits
0
none known

Summary

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 4.1-ESV before 4.1-ESV-R2 allows remote attackers to execute arbitrary commands via shell metacharacters in a hostname obtained from a DHCP message, as demonstrated by a hostname that is provided to dhclient-script.

Patch / fix

  • isc-dhcp Debian 13, Debian 12 4.1.1-P1-16.1

debian advisories DEBIAN-CVE-2011-0997

  • dhcp RHEL 4 7:3.0.1-67.el4
  • dhcp RHEL 5 12:3.0.5-23.el5_6.4
  • dhcp RHEL 6 12:4.1.1-12.P1.el6_0.4
  • dhclient RHEL 4 7:3.0.1-67.el4
  • dhclient RHEL 5 12:3.0.5-23.el5_6.4
  • dhclient RHEL 6 12:4.1.1-12.P1.el6_0.4
  • libdhcp4client RHEL 5 12:3.0.5-23.el5_6.4
  • dhcp RHEL 3 ELS 7:3.0.1-10.3_EL3

red hat advisories RHSA-2011:0840RHSA-2011:0428

  • dhcp openSUSE Tumbleweed 4.3.3.P1-3.1

opensuse advisories openSUSE-SU-2024:10358-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2011-0997 updated cvss 7.9

dhclient: insufficient sanitization of certain DHCP response values

  • Red Hat Enterprise Linux (v. 5.6.z server) dhcp 3.0.5-23.el5_6.4, dhclient 3.0.5-23.el5_6.4, libdhcp4client 3.0.5-23.el5_6.4
    fixed: vendor fix RHSA-2011:0428
  • Red Hat Enterprise Linux AS (v. 3 ELS) dhcp 3.0.1-10.3_EL3, dhclient 3.0.1-10.3_EL3
    fixed: vendor fix RHSA-2011:0840
  • Red Hat Enterprise Linux AS version 4 dhcp 3.0.1-67.el4, dhclient 3.0.1-67.el4 Red Hat Enterprise Linux Desktop (v. 6) dhcp 4.1.1-12.P1.el6_0.4, dhclient 4.1.1-12.P1.el6_0.4 Red Hat Enterprise Linux Desktop Optional (v. 6) dhcp 4.1.1-12.P1.el6_0.4 Red Hat Enterprise Linux Desktop version 4 dhcp 3.0.1-67.el4, dhclient 3.0.1-67.el4
    fixed: vendor fix RHSA-2011:0428
  • Red Hat Enterprise Linux ES (v. 3 ELS) dhcp 3.0.1-10.3_EL3, dhclient 3.0.1-10.3_EL3
    fixed: vendor fix RHSA-2011:0840
  • Red Hat Enterprise Linux ES version 4 dhcp 3.0.1-67.el4, dhclient 3.0.1-67.el4 Red Hat Enterprise Linux HPC Node (v. 6) dhcp 4.1.1-12.P1.el6_0.4, dhclient 4.1.1-12.P1.el6_0.4 Red Hat Enterprise Linux HPC Node Optional (v. 6) dhcp 4.1.1-12.P1.el6_0.4 Red Hat Enterprise Linux Server (v. 6) dhcp 4.1.1-12.P1.el6_0.4, dhclient 4.1.1-12.P1.el6_0.4 Red Hat Enterprise Linux Server Optional (v. 6) dhcp 4.1.1-12.P1.el6_0.4 Red Hat Enterprise Linux Workstation (v. 6) dhcp 4.1.1-12.P1.el6_0.4, dhclient 4.1.1-12.P1.el6_0.4
    +2 more products
    Red Hat Enterprise Linux Workstation Optional (v. 6) dhcp 4.1.1-12.P1.el6_0.4 Red Hat Enterprise Linux WS version 4 dhcp 3.0.1-67.el4, dhclient 3.0.1-67.el4
    fixed: vendor fix RHSA-2011:0428

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

84.57% chance of exploitation in the next 30 days, higher than 99.7% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • exploit-db.com https://www.exploit-db.com/exploits/37623/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 2.0 7.5 AV:N/AC:L/Au:N/C:P/I:P/A:P

Classification

Weakness
  • CWE-20 Improper Input Validation

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.