How severe is CVE-2020-3309?

CVE-2020-3309 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-2020-3309 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-3309?

CVE-2020-3309 affects Cisco Firepower Device Manager On-box. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-3309?

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-2020-3309 published?

CVE-2020-3309 was published on 2020-05-06 and last updated on 2026-06-17.

CVE-2020-3309

CVE-2020-3309 is a high-severity vulnerability in Cisco Firepower Device Manager On-box 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-787.

Key facts

Severity: High (CVSS 3.x base score 7.2)
CVSS v2: 9.0
EPSS exploit prediction: 2% (75th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Cisco Firepower Device Manager On-box
Published: 2020-05-06
Last modified: 2026-06-17

Description

A vulnerability in Cisco Firepower Device Manager (FDM) On-Box software could allow an authenticated, remote attacker to overwrite arbitrary files on the underlying operating system of an affected device. The vulnerability is due to improper input validation. An attacker could exploit this vulnerability by uploading a malicious file to an affected device. A successful exploit could allow the attacker to overwrite arbitrary files on as well as modify the underlying operating system of an affected device.

Frequently asked questions

What is CVE-2020-3309?: A vulnerability in Cisco Firepower Device Manager (FDM) On-Box software could allow an authenticated, remote attacker to overwrite arbitrary files on the underlying operating system of an affected device. The vulnerability is due to improper input validation. An attacker could exploit this vulnerability by uploading a malicious file to an affected device. A successful exploit could allow the attacker to overwrite arbitrary files on as well as modify the underlying operating system of an affected device.
How severe is CVE-2020-3309?: CVE-2020-3309 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-2020-3309 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3309?: CVE-2020-3309 affects Cisco Firepower Device Manager On-box. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-3309?: 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-2020-3309 published?: CVE-2020-3309 was published on 2020-05-06 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fdmfo-HvPWKxDe

Affected products (1)

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

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