CVE-2019-12789
By attaching a UART adapter to the UART pins on the system board, an attacker can use a special key sequence (Ctrl-\) to obtain a shell with root privileges.
Does this matter?
Lower severity and a low EPSS score (0.57%). Track it; it rarely justifies an emergency change on its own.
Description
An issue was discovered on Actiontec T2200H T2200H-31.128L.08 devices, as distributed by Telus. By attaching a UART adapter to the UART pins on the system board, an attacker can use a special key sequence (Ctrl-\) to obtain a shell with root privileges. After gaining root access, the attacker can mount the filesystem read-write and make permanent modifications to the device including bricking of the device, disabling vendor management of the device, preventing automatic upgrades, and permanently installing malicious code on the device.
- CVSS 3.0
- 6.8 MEDIUMCVSS:3.0/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.57% probability · 47th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Affected
- actiontec/t2200h firmware
- Source
- cve@mitre.org
EPSS 0.6% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://seclists.org/fulldisclosure/2019/Jun/10Exploit, Mailing List, Third Party Advisory
- https://www.actiontec.com/blog/Third Party Advisory
- http://seclists.org/fulldisclosure/2019/Jun/10Exploit, Mailing List, Third Party Advisory
- https://www.actiontec.com/blog/Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.