# 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 |

---

Data as of 2026-11-08T19:12:23Z 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

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.
