SYNful Knock
MITRE ATT&CK: S0519 View on attack.mitre.org
Aliases: SYNful Knock
- First seen
- 2015-09-15 00:00:00
- Malware type
- backdoor, rootkit
- Family
- Malware family
- Operating systems
- network-devices
- Profile updated
- 2026-07-07 15:28:13
Targeted industries: government-and-public-sector
Targeted regions: country_code:us country_code:cn country_code:ru
Context
SYNful Knock is a stealthy modification of the operating system of network devices that can be used to maintain persistence within a victim's network and provide new capabilities to the adversary.
Detection coverage
- 1 Sigma rules
Malware & tools used
- Patch System Image (attack-pattern)
- Traffic Signaling (attack-pattern)
- Network Device Authentication (attack-pattern)
Reports & references
- MITRE ATT&CK — S0519 (report)
- blogs.cisco.com — Evolution Of Attacks On Cisco Ios Devices (report)
- cloud.google.com — Synful Knock Acis (report)