CVE-2026-121818 PUBLISHED

About Time Technologies｜Herowatch Go - Security Misconfiguration

Assigner: twcert
Reserved: 04.11.2026 Published: 04.11.2026 Updated: 04.11.2026

Herowatch Mini developed by About Time Technologies has a system signing vulnerability. Authenticated local attackers can exploit a publicly available test key to sign malicious programs, allowing them to elevate privileges and execute arbitrary code.

CVSS Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CVSS Score: 8.5

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Local	Confidentiality	High	Confidentiality	None
Attack Complexity	Low	Integrity	High	Integrity	None
Attack Requirements	None	Availability	High	Availability	None
Privileges Required	Low
User Interaction	None

CVSS 4.0

CVSS Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS Score: 7.8

Attack Vector	Local	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	High
Privileges Required	Low	Integrity Impact	High
User Interaction	None	Availability Impact	High

CVSS 3.1

Product Status

Vendor	About Time Technologies
Product	Herowatch Go
Versions	Default: unaffected Version all is affected

Solutions

The product is no longer maintained. Users are advised to replace it with a supported device.

References

Problem Types

CWE-1394 Use of Default Cryptographic Key CWE