CVE-2021-1542: Cisco Small Business 220 Series Smart Switches Vulnerabilities

Severity: high (CVSS 8.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-06-16 · updated 2026-06-17
Weakness: CWE-287

Description

Multiple vulnerabilities in the web-based management interface of Cisco Small Business 220 Series Smart Switches could allow an attacker to do the following: Hijack a user session Execute arbitrary commands as a root user on the underlying operating system Conduct a cross-site scripting (XSS) attack Conduct an HTML injection attack For more information about these vulnerabilities, see the Details section of this advisory.

Affected products

Cisco Sf220-24 Firmware: before 1.2.0.6 — fixed in 1.2.0.6
Cisco Sf220-24P Firmware: before 1.2.0.6 — fixed in 1.2.0.6
Cisco Sf220-48 Firmware: before 1.2.0.6 — fixed in 1.2.0.6
Cisco Sf220-48P Firmware: before 1.2.0.6 — fixed in 1.2.0.6
Cisco Sg220-26 Firmware: before 1.2.0.6 — fixed in 1.2.0.6
Cisco Sg220-26P Firmware: before 1.2.0.6 — fixed in 1.2.0.6
Cisco Sg220-28Mp Firmware: before 1.2.0.6 — fixed in 1.2.0.6
Cisco Sg220-50 Firmware: before 1.2.0.6 — fixed in 1.2.0.6
Cisco Sg220-50P Firmware: before 1.2.0.6 — fixed in 1.2.0.6

How to fix

Upgrade to a fixed version: Cisco Sf220-24 Firmware 1.2.0.6; Cisco Sf220-24P Firmware 1.2.0.6; Cisco Sf220-48 Firmware 1.2.0.6; Cisco Sf220-48P Firmware 1.2.0.6; Cisco Sg220-26 Firmware 1.2.0.6; Cisco Sg220-26P Firmware 1.2.0.6; Cisco Sg220-28Mp Firmware 1.2.0.6; Cisco Sg220-50 Firmware 1.2.0.6; Cisco Sg220-50P Firmware 1.2.0.6. Check the vendor advisory for mitigations.

References

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