CVE-2021-1493

CVE-2021-1493 is a high-severity vulnerability in Cisco Firepower Threat Defense with a CVSS 3.x base score of 8.5. 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-120.

Key facts

Description

A vulnerability in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, remote attacker to cause a buffer overflow on an affected system. The vulnerability is due to insufficient boundary checks for specific data that is provided to the web services interface of an affected system. An attacker could exploit this vulnerability by sending a malicious HTTP request. A successful exploit could allow the attacker to cause a buffer overflow condition on the affected system, which could disclose data fragments or cause the device to reload, resulting in a denial of service (DoS) condition.

Frequently asked questions

What is CVE-2021-1493?
A vulnerability in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, remote attacker to cause a buffer overflow on an affected system. The vulnerability is due to insufficient boundary checks for specific data that is provided to the web services interface of an affected system. An attacker could exploit this vulnerability by sending a malicious HTTP request. A successful exploit could allow the attacker to cause a buffer overflow condition on the affected system, which could disclose data fragments or cause the device to reload, resulting in a denial of service (DoS) condition.
How severe is CVE-2021-1493?
CVE-2021-1493 has a CVSS 3.x base score of 8.5, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability high.
Is CVE-2021-1493 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-1493?
CVE-2021-1493 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-2021-1493?
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-2021-1493 published?
CVE-2021-1493 was published on 2021-04-29 and last updated on 2026-06-17.

References

Affected products (2)

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