Vulnerability · Published Oct 13, 2026 · Assigned by redhat

CVE-2026-88833Busybox: busybox: udhcpc integer underflow in dhcp packet length calculation causes denial of service

Medium 6.5

In plain English

A medium-severity security flaw in Red Hat Hardened Images from Red Hat. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 9% of all known vulnerabilities).

Severity (CVSS 3.1)6.5Medium

Exploit odds (30 days)0.2%top 91.4% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

A flaw was found in BusyBox's udhcpc DHCP client. When processing raw DHCP packets, the client replaces the validated packet length with an attacker-controlled value from the IP header without re-validating the minimum size. This leads to an integer underflow when subtracting header sizes, causing a subsequent memory copy with a massively oversized length. An attacker on the same network segment can send a specially crafted packet to crash the DHCP client, resulting in denial of service and loss of network connectivity.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:12	busybox	no fix listed	DEBIAN-CVE-2026-88833
Debian:13	busybox	no fix listed	DEBIAN-CVE-2026-88833
Debian:14	busybox	no fix listed	DEBIAN-CVE-2026-88833
Ubuntu:22.04:LTS	busybox	no fix listed	UBUNTU-CVE-2026-88833
Ubuntu:24.04:LTS	busybox	no fix listed	UBUNTU-CVE-2026-88833
Ubuntu:26.04:LTS	busybox	no fix listed	UBUNTU-CVE-2026-88833
Ubuntu:26.10	busybox	no fix listed	UBUNTU-CVE-2026-88833

Affected products (as reported)

Vendor	Product	Versions
Red Hat	Red Hat Hardened Images	see references

Weakness: CWE-191 · Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

https://access.redhat.com/security/cve/CVE-2026-88833 vdb-entry, x_refsource_REDHAT
RHBZ#2531347 issue-tracking, x_refsource_REDHAT