CVE-2022-20737

Cisco Adaptive Security Appliance Software Clientless SSL VPN Heap Overflow Vulnerability

HIGH
7.1
CVSS Score
Published: May 3, 2022 at 03:16 AM UTC
Updated: June 17, 2026 at 04:24 AM UTC
1 product affected across 1 vendorAdaptive Security Appliance

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 handler for HTTP authentication for resources accessed through the Clientless SSL VPN portal of Cisco Adaptive Security Appliance (ASA) Software could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device or to obtain portions of process memory from an affected device. This vulnerability is due to insufficient bounds checking when parsing specific HTTP authentication messages. An attacker could exploit this vulnerability by sending malicious traffic to an affected device acting as a VPN Gateway. To send this malicious traffic, an attacker would need to control a web server that can be accessed through the Clientless SSL VPN portal. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition, or to retrieve bytes from the device process memory that may contain sensitive information.

Affected

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

v < 9.12.4.389.13.0 ≤ v < 9.14.49.15.0 ≤ v < 9.15.1.219.16.0 ≤ v < 9.16.2.149.17.0 ≤ v < 9.17.1.7
Affected range stops below 9.12.4.38, so it looks safe — our inference, not a vendor statement
Affected range stops below 9.14.4, so it looks safe — our inference, not a vendor statement
Affected range stops below 9.15.1.21, so it looks safe — our inference, not a vendor statement
Affected range stops below 9.16.2.14, so it looks safe — our inference, not a vendor statement
Affected range stops below 9.17.1.7, so it looks safe — our inference, not a vendor statement

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-122CWE-787

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