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{"acknowledgement": "Red Hat would like to thank Shubham Raj (Causal Security) for reporting this issue.", "bugzilla": {"description": "busybox: busybox: udhcpc integer underflow in DHCP packet length calculation causes denial of service", "id": "2531347", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2531347"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.5", "cvss3_scoring_vector": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-191", "details": ["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."], "mitigation": {"lang": "en:us", "value": "If feasible, use udhcpc in LISTEN_KERNEL mode instead of LISTEN_RAW, or use an alternative DHCP client (dhclient, systemd-networkd). Restrict DHCP traffic on the local segment (for example DHCP snooping on switches)."}, "name": "CVE-2026-88833", "package_state": [{"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "busybox", "product_name": "Red Hat Hardened Images"}], "public_date": "2026-10-13T13:49:21Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-88833\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-88833"], "statement": "This flaw allows an attacker on the same Layer 2 network segment to crash the BusyBox udhcpc DHCP client, resulting in loss of network configuration. Fedora uses NetworkManager with dhclient as the default DHCP client rather than udhcpc, making this vulnerability unlikely to affect standard Fedora installations.", "threat_severity": "Moderate"}