CVE-2016-6301

Severity: high (CVSS 7.5 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 9.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2016-12-09 · updated 2026-06-17
Weakness: CWE-399

Description

The recv_and_process_client_pkt function in networking/ntpd.c in busybox allows remote attackers to cause a denial of service (CPU and bandwidth consumption) via a forged NTP packet, which triggers a communication loop.

Affected products

busybox: before 1.25.1 — fixed in 1.25.1

How to fix

Upgrade to a fixed version: busybox 1.25.1. Check the vendor advisory for mitigations.

References

http://packetstormsecurity.com/files/153278/WAGO-852-Industrial-Managed-Switch-Series-Code-Execution-Hardcoded-Credentials.html
http://packetstormsecurity.com/files/154361/Cisco-Device-Hardcoded-Credentials-GNU-glibc-BusyBox.html
http://seclists.org/fulldisclosure/2019/Jun/18
http://seclists.org/fulldisclosure/2019/Sep/7
http://seclists.org/fulldisclosure/2020/Aug/20
http://seclists.org/fulldisclosure/2020/Mar/15
http://www.openwall.com/lists/oss-security/2016/08/03/7
http://www.securityfocus.com/bid/92277
https://bugzilla.redhat.com/show_bug.cgi?id=1363710
https://git.busybox.net/busybox/commit/?id=150dc7a2b483b8338a3e185c478b4b23ee884e71
https://seclists.org/bugtraq/2019/Jun/14
https://seclists.org/bugtraq/2019/Sep/7

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