How severe is CVE-2021-1518?

CVE-2021-1518 has a CVSS 3.x base score of 6.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2021-1518 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-1518?

CVE-2021-1518 affects Cisco Firepower Device Manager On-box. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-1518?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-1518 published?

CVE-2021-1518 was published on 2021-07-22 and last updated on 2026-06-17.

CVE-2021-1518

CVE-2021-1518 is a medium-severity vulnerability in Cisco Firepower Device Manager On-box with a CVSS 3.x base score of 6.3. 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-94.

Key facts

Severity: Medium (CVSS 3.x base score 6.3)
CVSS v2: 9.0
EPSS exploit prediction: 2% (77th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-94
Affected product: Cisco Firepower Device Manager On-box
Published: 2021-07-22
Last modified: 2026-06-17

Description

A vulnerability in the REST API of Cisco Firepower Device Manager (FDM) On-Box Software could allow an authenticated, remote attacker to execute arbitrary code on the underlying operating system of an affected device. This vulnerability is due to insufficient sanitization of user input on specific REST API commands. An attacker could exploit this vulnerability by sending a crafted HTTP request to the API subsystem of an affected device. A successful exploit could allow the attacker to execute arbitrary code on the underlying operating system. To exploit this vulnerability, an attacker would need valid low-privileged user credentials.

Frequently asked questions

What is CVE-2021-1518?: A vulnerability in the REST API of Cisco Firepower Device Manager (FDM) On-Box Software could allow an authenticated, remote attacker to execute arbitrary code on the underlying operating system of an affected device. This vulnerability is due to insufficient sanitization of user input on specific REST API commands. An attacker could exploit this vulnerability by sending a crafted HTTP request to the API subsystem of an affected device. A successful exploit could allow the attacker to execute arbitrary code on the underlying operating system. To exploit this vulnerability, an attacker would need valid low-privileged user credentials.
How severe is CVE-2021-1518?: CVE-2021-1518 has a CVSS 3.x base score of 6.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2021-1518 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-1518?: CVE-2021-1518 affects Cisco Firepower Device Manager On-box. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-1518?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-1518 published?: CVE-2021-1518 was published on 2021-07-22 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fdm-rce-Rx6vVurq

Affected products (1)

cpe:2.3:a:cisco:firepower_device_manager_on-box:*:*:*:*:*:*:*:*

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