CVE-2026-88833
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk8th percentile - higher than 8% of all known CVEs
Summary
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.
Risk Assessment
An attacker on the same network can remotely crash the DHCP client, causing the device to lose network connectivity. The risk applies to devices using BusyBox udhcpc on untrusted network segments.
Recommendation
Upgrade BusyBox to a version containing the fix when available. Until then, consider network segmentation and restricting DHCP traffic from untrusted sources.
Other vulnerabilities in BusyBox
See all- CVE-2026-88836Unknown
This CVE candidate has been rejected by Red Hat Product Security because it is not a security vulnerability. BusyBox internal TLS is intentionally minimal and documents in FEATURE_WGET_HTTPS that it does not verify peer identity or provide full TLS security; missing Finished verify_data checking is consistent with that documented design and does not cross a separate security boundary warranting a CVE.
- CVE-2024-58251Low
In netstat in BusyBox through 1.37.0, local users can launch a network application with an argv[0] containing an ANSI terminal escape sequence, leading to a denial of service (terminal locked up) when netstat is used by a victim.
- CVE-2023-42365Medium
A use-after-free vulnerability was discovered in BusyBox v.1.36.1 via a crafted awk pattern in the awk.c copyvar function.
- CVE-2023-42364Medium
A use-after-free vulnerability exists in BusyBox v1.36.1 in the evaluate function in awk.c. An attacker can cause a denial of service via a crafted awk pattern.
- CVE-2023-42363Medium
A use-after-free vulnerability was discovered in the xasprintf function in xfuncs_printf.c:344 in BusyBox v.1.36.1.
- CVE-2017-16544High
In the add_match function in libbb/lineedit.c in BusyBox through 1.27.2, the tab autocomplete feature does not sanitize filenames, potentially leading to executing any escape sequences in the terminal.
- CVE-2011-5325High
Directory traversal vulnerability in the BusyBox implementation of tar before version 1.22.0 v5 allows remote attackers to point to files outside the current working directory via a symlink.
- CVE-2016-2147High
Integer overflow in the DHCP client (udhcpc) in BusyBox before version 1.25.0 allows remote attackers to cause a denial of service (crash) via a malformed RFC1035-encoded domain name, leading to an out-of-bounds heap write.
- CVE-2016-6301High
The recv_and_process_client_pkt function in networking/ntpd.c in busybox allows remote attackers to cause a denial of service via a forged NTP packet, triggering a communication loop.
- CVE-2026-88841Low
The vulnerability in BusyBox affects the write_status_file() function in the dpkg tool. Failure to reset a stale field cursor between package stanzas leads to out-of-bounds reads and corruption of the status file when removing multiple packages.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS