CVE-2021-1493

Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Buffer Overflow Denial of Service Vulnerability

HIGH
7.1
CVSS Score
Published: April 29, 2021 at 05:31 PM UTC
Updated: August 11, 2026 at 07:37 PM UTC
2 products affected across 1 vendorAdaptive Security ApplianceSecure Firewall Threat Defense

Using Cisco Adaptive Security Appliance (ASA) Software by Cisco?

Get instant alerts when new vulnerabilities affect Cisco Adaptive Security Appliance (ASA) Software - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH7.1
Exploit prediction
EPSS 1%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

9.10 ≤ v < 9.12.4.139.13 ≤ v < 9.13.1.219.14 ≤ v < 9.14.2.89.15 ≤ v < 9.15.1.79.8 ≤ v < 9.8.4.349.9 ≤ v < 9.9.2.85
Affected range stops below 9.12.4.13, so it looks safe — our inference, not a vendor statement
Affected range stops below 9.13.1.21, so it looks safe — our inference, not a vendor statement
Affected range stops below 9.14.2.8, so it looks safe — our inference, not a vendor statement
Affected range stops below 9.15.1.7, so it looks safe — our inference, not a vendor statement
Affected range stops below 9.8.4.34, so it looks safe — our inference, not a vendor statement
Affected range stops below 9.9.2.85, so it looks safe — our inference, not a vendor statement
v < 6.4.0.126.5.0 ≤ v < 6.6.36.7.0 ≤ v < 6.7.0.1

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-120

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card