# CVE-2021-25217: dhcp-libs: The Dynamic Host Configuration Protocol (DHCP) is a protocol that allows individual devices on an IP network to get t...

CVE-2021-25217 is fixed in 11 products on 1 platform, first by isc-dhcp-client 4.3.5-3ubuntu7.3, released May 25, 2021. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-25217
- Priority: High
- CVSS: 8.8 (Important)
- EPSS: 0.0612
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: May 25, 2021

## Description

The Dynamic Host Configuration Protocol (DHCP) is a protocol that allows individual devices on an IP network to get their own network configuration information, including an IP address, a subnet mask, and a broadcast address. The dhcp packages provide a relay agent and ISC DHCP service required to enable and administer DHCP on a network.  Security Fix(es):  * dhcp: stack-based buffer overflow when parsing statements with colon-separated hex digits in config or lease files in dhcpd and dhclient (CVE-2021-25217)  For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | dhcp-client RHEL 8 | 12:4.3.6-44.el8_4.1 | [RHSA-2021:2359](https://patchblox.com/security/data/fix/linux/rhsa-2021-2359.md) | Jun 9, 2021 |
| Linux | dhcp-client ol 8 | 12:4.3.6-44.el8_4.1 | [ELSA-2021-2359](https://patchblox.com/security/data/fix/linux/elsa-2021-2359.md) | Jun 10, 2021 |
| Linux | dhcp-common RHEL 8 | 12:4.3.6-44.el8_4.1 | [RHSA-2021:2359](https://patchblox.com/security/data/fix/linux/rhsa-2021-2359.md) | Jun 9, 2021 |
| Linux | dhcp-common ol 8 | 12:4.3.6-44.el8_4.1 | [ELSA-2021-2359](https://patchblox.com/security/data/fix/linux/elsa-2021-2359.md) | Jun 10, 2021 |
| Linux | dhcp-libs RHEL 8 | 12:4.3.6-44.el8_4.1 | [RHSA-2021:2359](https://patchblox.com/security/data/fix/linux/rhsa-2021-2359.md) | Jun 9, 2021 |
| Linux | dhcp-libs ol 8 | 12:4.3.6-44.el8_4.1 | [ELSA-2021-2359](https://patchblox.com/security/data/fix/linux/elsa-2021-2359.md) | Jun 10, 2021 |
| Linux | dhcp-relay RHEL 8 | 12:4.3.6-44.el8_4.1 | [RHSA-2021:2359](https://patchblox.com/security/data/fix/linux/rhsa-2021-2359.md) | Jun 9, 2021 |
| Linux | dhcp-relay ol 8 | 12:4.3.6-44.el8_4.1 | [ELSA-2021-2359](https://patchblox.com/security/data/fix/linux/elsa-2021-2359.md) | Jun 10, 2021 |
| Linux | dhcp-server RHEL 8 | 12:4.3.6-44.el8_4.1 | [RHSA-2021:2359](https://patchblox.com/security/data/fix/linux/rhsa-2021-2359.md) | Jun 9, 2021 |
| Linux | dhcp-server ol 8 | 12:4.3.6-44.el8_4.1 | [ELSA-2021-2359](https://patchblox.com/security/data/fix/linux/elsa-2021-2359.md) | Jun 10, 2021 |
| Linux | isc-dhcp-client Ubuntu 18.04.6 LTS (bionic) | 4.3.5-3ubuntu7.3 | [isc-dhcp-client 4.3.5-3ubuntu7.3](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-isc-dhcp-client-4.3.5-3ubuntu7.3.md) | May 25, 2021 |
| Linux | isc-dhcp-client Ubuntu 20.04 LTS (focal) | 4.4.1-2.1ubuntu5.20.04.2 | [isc-dhcp-client 4.4.1-2.1ubuntu5.20.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-isc-dhcp-client-4.4.1-2.1ubuntu5.20.04.2.md) | May 25, 2021 |
| Linux | isc-dhcp-client-ddns Ubuntu 18.04.6 LTS (bionic) | 4.3.5-3ubuntu7.3 | [isc-dhcp-client-ddns 4.3.5-3ubuntu7.3](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-isc-dhcp-client-ddns-4.3.5-3ubuntu7.3.md) | May 25, 2021 |
| Linux | isc-dhcp-client-ddns Ubuntu 20.04 LTS (focal) | 4.4.1-2.1ubuntu5.20.04.2 | [isc-dhcp-client-ddns 4.4.1-2.1ubuntu5.20.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-isc-dhcp-client-ddns-4.4.1-2.1ubuntu5.20.04.2.md) | May 25, 2021 |
| Linux | isc-dhcp-common Ubuntu 18.04.6 LTS (bionic) | 4.3.5-3ubuntu7.3 | [isc-dhcp-common 4.3.5-3ubuntu7.3](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-isc-dhcp-common-4.3.5-3ubuntu7.3.md) | May 25, 2021 |
| Linux | isc-dhcp-common Ubuntu 20.04 LTS (focal) | 4.4.1-2.1ubuntu5.20.04.2 | [isc-dhcp-common 4.4.1-2.1ubuntu5.20.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-isc-dhcp-common-4.4.1-2.1ubuntu5.20.04.2.md) | May 25, 2021 |
| Linux | isc-dhcp-relay Ubuntu 18.04.6 LTS (bionic) | 4.3.5-3ubuntu7.3 | [isc-dhcp-relay 4.3.5-3ubuntu7.3](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-isc-dhcp-relay-4.3.5-3ubuntu7.3.md) | May 25, 2021 |
| Linux | isc-dhcp-relay Ubuntu 20.04 LTS (focal) | 4.4.1-2.1ubuntu5.20.04.2 | [isc-dhcp-relay 4.4.1-2.1ubuntu5.20.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-isc-dhcp-relay-4.4.1-2.1ubuntu5.20.04.2.md) | May 25, 2021 |
| Linux | isc-dhcp-server Ubuntu 18.04.6 LTS (bionic) | 4.3.5-3ubuntu7.3 | [isc-dhcp-server 4.3.5-3ubuntu7.3](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-isc-dhcp-server-4.3.5-3ubuntu7.3.md) | May 25, 2021 |
| Linux | isc-dhcp-server Ubuntu 20.04 LTS (focal) | 4.4.1-2.1ubuntu5.20.04.2 | [isc-dhcp-server 4.4.1-2.1ubuntu5.20.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-isc-dhcp-server-4.4.1-2.1ubuntu5.20.04.2.md) | May 25, 2021 |
| Linux | isc-dhcp-server-ldap Ubuntu 18.04.6 LTS (bionic) | 4.3.5-3ubuntu7.3 | [isc-dhcp-server-ldap 4.3.5-3ubuntu7.3](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-isc-dhcp-server-ldap-4.3.5-3ubuntu7.3.md) | May 25, 2021 |
| Linux | isc-dhcp-server-ldap Ubuntu 20.04 LTS (focal) | 4.4.1-2.1ubuntu5.20.04.2 | [isc-dhcp-server-ldap 4.4.1-2.1ubuntu5.20.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-isc-dhcp-server-ldap-4.4.1-2.1ubuntu5.20.04.2.md) | May 25, 2021 |

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Data as of 2026-11-07T06:34:28Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo