How severe is CVE-2021-1541?

CVE-2021-1541 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-1541 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (95th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-1541?

CVE-2021-1541 primarily affects Cisco Sf220-24 Firmware. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-1541?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-1541 published?

CVE-2021-1541 was published on 2021-06-16 and last updated on 2026-06-17.

CVE-2021-1541

CVE-2021-1541 is a high-severity vulnerability in Cisco Sf220-24 Firmware with a CVSS 3.x base score of 7.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: High (CVSS 3.x base score 7.2)
CVSS v2: 9.0
EPSS exploit prediction: 9% (95th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Cisco Sf220-24 Firmware
Published: 2021-06-16
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2021-1541?: 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.
How severe is CVE-2021-1541?: CVE-2021-1541 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-1541 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (95th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-1541?: CVE-2021-1541 primarily affects Cisco Sf220-24 Firmware. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-1541?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-1541 published?: CVE-2021-1541 was published on 2021-06-16 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ciscosb-multivulns-Wwyb7s5E

Affected products (9)

cpe:2.3:o:cisco:sf220-24_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:sf220-24p_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:sf220-48_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:sf220-48p_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:sg220-26_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:sg220-26p_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:sg220-28mp_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:sg220-50_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:sg220-50p_firmware:*:*:*:*:*:*:*:*

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Other CWE-287 (Improper Authentication) vulnerabilities

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