CVE-2021-1445
CVE-2021-1445 is a high-severity vulnerability in Cisco Firepower Threat Defense with a CVSS 3.x base score of 8.6. 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 8.6)
- CVSS v2: 5.0
- EPSS exploit prediction: 2% (74th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Cisco Firepower Threat Defense
- Published:
- Last modified:
Description
Multiple vulnerabilities in Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. These vulnerabilities are due to lack of proper input validation of the HTTPS request. An attacker could exploit these vulnerabilities by sending a crafted HTTPS request to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Note: This vulnerability affects only specific AnyConnect and WebVPN configurations. For more information, see the Vulnerable Products section.
Frequently asked questions
- What is CVE-2021-1445?
- Multiple vulnerabilities in Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. These vulnerabilities are due to lack of proper input validation of the HTTPS request. An attacker could exploit these vulnerabilities by sending a crafted HTTPS request to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Note: This vulnerability affects only specific AnyConnect and WebVPN configurations. For more information, see the Vulnerable Products section.
- How severe is CVE-2021-1445?
- CVE-2021-1445 has a CVSS 3.x base score of 8.6, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2021-1445 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-1445?
- CVE-2021-1445 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-2021-1445?
- 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-2021-1445 published?
- CVE-2021-1445 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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