CVE-2020-16134

Severity: high (CVSS 8.0 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-08-04 · updated 2026-06-17

Description

An issue was discovered on Swisscom Internet Box 2, Internet Box Standard, Internet Box Plus prior to 10.04.38, Internet Box 3 prior to 11.01.20, and Internet Box light prior to 08.06.06. Given the (user-configurable) credentials for the local Web interface or physical access to a device's plus or reset button, an attacker can create a user with elevated privileges on the Sysbus-API. This can then be used to modify local or remote SSH access, thus allowing a login session as the superuser.

Affected products

Swisscom Internet-Box 2 Firmware: before 10.04.38 — fixed in 10.04.38
Swisscom Internet-Box 3 Firmware: before 11.01.20 — fixed in 11.01.20
Swisscom Internet-Box Light Firmware: before 08.06.06 — fixed in 08.06.06
Swisscom Internet-Box Plus Firmware: before 10.04.38 — fixed in 10.04.38
Swisscom Internet-Box Standard Firmware: before 10.04.38 — fixed in 10.04.38

How to fix

Upgrade to a fixed version: Swisscom Internet-Box 2 Firmware 10.04.38; Swisscom Internet-Box 3 Firmware 11.01.20; Swisscom Internet-Box Light Firmware 08.06.06; Swisscom Internet-Box Plus Firmware 10.04.38; Swisscom Internet-Box Standard Firmware 10.04.38. Check the vendor advisory for mitigations.

References

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