dhcp: DoS due to processing certain regular expressions
Published Dec 8, 2011
5.0
MEDIUMCVSS 2.0
EPSS 15.22%
Description
dhcpd in ISC DHCP 4.x before 4.2.3-P1 and 4.1-ESV before 4.1-ESV-R4 does not properly handle regular expressions in dhcpd.conf, which allows remote attackers to cause a denial of service (daemon crash) via a crafted request packet.
Affected products
No data.
Configuration 1
- 4.0
- 4.0.0
- 4.0.1
- 4.0.1
- 4.0.1
- 4.0.2
- 4.0.2
- 4.0.2
- 4.0.2
- 4.0.2
- 4.0.3
- 4.0.3
- 4.0.3
- 4.1.1
- 4.1.1
- 4.1.2
- 4.2.0
- 4.2.0
- 4.2.0
- 4.2.0
- 4.2.0
- 4.2.0
- 4.2.0
- 4.2.1
- 4.2.1
- 4.2.1
- 4.2.2
- 4.2.2
- 4.2.2
- 4.2.3
Configuration 2
Configuration 3
- 11.04
- 11.10
Configuration 4
- 6.0
- 7.0
No data.
Red Hat Enterprise Linux 6
dhcp-12:4.1.1-25.P1.el6_2.1
Fixed · RHSA-2011:1819
Red Hat Enterprise Linux 4
dhcp
Not affected
Red Hat Enterprise Linux 5
dhcp
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 6 | dhcp-12:4.1.1-25.P1.el6_2.1 | Fixed | RHSA-2011:1819 |
| Red Hat Enterprise Linux 4 | dhcp | Not affected | n/a |
| Red Hat Enterprise Linux 5 | dhcp | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This issue did not affect the versions of dhcp as shipped with Red Hat Enterprise Linux 4 and 5.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
No CVSS v3.0 score for this CVE.
AV:N/AC:L/Au:N/C:N/I:N/A:P
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (16 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 15.22% (0.15219) | 96.66th | v5 (v2026.06.15) |
| Jun 15, 2026 | 15.48% (0.15478) | 96.37th | v5 (v2026.06.15) |
| Apr 29, 2026 | 32.27% (0.32265) | 96.85th | v4 (v2025.03.14) |
| Mar 21, 2026 | 26.92% (0.26920) | 96.31th | v4 (v2025.03.14) |
| Aug 8, 2025 | 32.27% (0.32265) | 96.66th | v4 (v2025.03.14) |
| Mar 30, 2025 | 34.28% (0.34285) | 96.63th | v4 (v2025.03.14) |
| Mar 29, 2025 | 39.46% (0.39463) | 95.92th | v4 (v2025.03.14) |
| Mar 19, 2025 | 34.28% (0.34285) | 96.47th | v4 (v2025.03.14) |
| Mar 17, 2025 | 31.84% (0.31841) | 96.41th | v4 (v2025.03.14) |
| Dec 12, 2024 | 2.84% (0.02837) | 91.06th | v3 (v2023.03.01) |
| Jun 7, 2024 | 2.84% (0.02837) | 90.70th | v3 (v2023.03.01) |
| Jul 8, 2023 | 2.02% (0.02021) | 87.34th | v3 (v2023.03.01) |
| May 5, 2023 | 2.84% (0.02837) | 89.16th | v3 (v2023.03.01) |
| Mar 7, 2023 | 3.97% (0.03966) | 90.65th | v3 (v2023.03.01) |
| Mar 6, 2023 | 23.60% (0.23599) | 96.71th | v2 (v2022.01.01) |
| Feb 4, 2022 | 23.60% (0.23599) | 94.79th | v2 (v2022.01.01) |
References (17)
- http://lists.fedoraproject.org/pipermail/package-announce/2011-December/070980.html vendor-advisoryx_refsource_FEDORAMailing ListThird Party Advisory
- http://lists.fedoraproject.org/pipermail/package-announce/2012-January/071549.html vendor-advisoryx_refsource_FEDORAMailing ListThird Party Advisory
- http://lists.opensuse.org/opensuse-updates/2011-12/msg00006.html vendor-advisoryx_refsource_SUSEMailing ListThird Party Advisory
- http://secunia.com/advisories/47153 third-party-advisoryx_refsource_SECUNIAThird Party Advisory
- http://secunia.com/advisories/47178 third-party-advisoryx_refsource_SECUNIAThird Party Advisory
- http://security.gentoo.org/glsa/glsa-201301-06.xml vendor-advisoryx_refsource_GENTOOThird Party Advisory
- http://www.debian.org/security/2012/dsa-2519 vendor-advisoryx_refsource_DEBIANThird Party Advisory
- http://www.mandriva.com/security/advisories?name=MDVSA-2011:182 vendor-advisoryx_refsource_MANDRIVAThird Party Advisory
- http://www.securityfocus.com/bid/50971 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- http://www.securitytracker.com/id?1026393 vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry
- http://www.ubuntu.com/usn/USN-1309-1 vendor-advisoryx_refsource_UBUNTUThird Party Advisory
- https://access.redhat.com/security/cve/CVE-2011-4539 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=761265 Issue Tracking
- https://exchange.xforce.ibmcloud.com/vulnerabilities/71680 vdb-entryx_refsource_XFThird Party AdvisoryVDB Entry
- https://nvd.nist.gov/vuln/detail/CVE-2011-4539
- https://www.cve.org/CVERecord?id=CVE-2011-4539
- https://www.isc.org/software/dhcp/advisories/cve-2011-4539 x_refsource_CONFIRMVendor Advisory
Change history (0)
No recorded changes yet.