CVE-2022-2929: DHCP memory leak

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2022-10-07 · updated 2026-06-17
Weakness: CWE-770

Description

In ISC DHCP 1.0 -> 4.4.3, ISC DHCP 4.1-ESV-R1 -> 4.1-ESV-R16-P1 a system with access to a DHCP server, sending DHCP packets crafted to include fqdn labels longer than 63 bytes, could eventually cause the server to run out of memory.

Affected products

Debian Linux: 10.0
Fedoraproject Fedora: 35, 36, 37
ISC DHCP: from 1.0.0 before 4.1-esv; from 4.2.0 through 4.4.3; 4.1-esv-r1, 4.1-esv-r10, 4.1-esv-r10_b1, 4.1-esv-r10_rc1, 4.1-esv-r10b1, 4.1-esv-r10rc1 (+23) — fixed in 4.1-esv

How to fix

Upgrade to a fixed version: ISC DHCP 4.1-esv. Check the vendor advisory for mitigations.

References

https://kb.isc.org/docs/cve-2022-2929
https://lists.debian.org/debian-lts-announce/2022/10/msg00015.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2SARIK7KZ7MGQIWDRWZFAOSQSPXY4GOU/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QQXYCIWUDILRCNBAIMVFCSGXBRKEPB4K/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T6IBFH4MRRNJQVWEKILQ6I6CXWW766FX/
https://security.gentoo.org/glsa/202305-22
https://kb.isc.org/docs/cve-2022-2929
https://lists.debian.org/debian-lts-announce/2022/10/msg00015.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2SARIK7KZ7MGQIWDRWZFAOSQSPXY4GOU/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QQXYCIWUDILRCNBAIMVFCSGXBRKEPB4K/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T6IBFH4MRRNJQVWEKILQ6I6CXWW766FX/
https://security.gentoo.org/glsa/202305-22

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