CVE-2021-1476
CVE-2021-1476 is a medium-severity vulnerability in Cisco Firepower Threat Defense with a CVSS 3.x base score of 6.7. 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-78.
Key facts
- Severity: Medium (CVSS 3.x base score 6.7)
- CVSS v2: 7.2
- EPSS exploit prediction: 0% (38th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-78
- Affected product: Cisco Firepower Threat Defense
- Published:
- Last modified:
Description
A vulnerability in the CLI of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, local attacker to execute arbitrary commands on the underlying operating system (OS) of an affected device. The vulnerability is due to insufficient input validation of commands that are supplied by the user. An attacker could exploit this vulnerability by authenticating to a device and submitting crafted input for specific commands. A successful exploit could allow the attacker to execute commands on the underlying OS with root privileges. To exploit this vulnerability, an attacker must have valid administrator-level credentials.
Frequently asked questions
- What is CVE-2021-1476?
- A vulnerability in the CLI of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, local attacker to execute arbitrary commands on the underlying operating system (OS) of an affected device. The vulnerability is due to insufficient input validation of commands that are supplied by the user. An attacker could exploit this vulnerability by authenticating to a device and submitting crafted input for specific commands. A successful exploit could allow the attacker to execute commands on the underlying OS with root privileges. To exploit this vulnerability, an attacker must have valid administrator-level credentials.
- How severe is CVE-2021-1476?
- CVE-2021-1476 has a CVSS 3.x base score of 6.7, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-1476 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-1476?
- CVE-2021-1476 primarily affects Cisco Firepower Threat Defense. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-1476?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-1476 published?
- CVE-2021-1476 was published on 2021-04-29 and last updated on 2026-06-17.
References
Affected products (2)
- cpe:2.3:a:cisco:firepower_threat_defense:*:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*
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