Every CVE Search/ Get API key

CVE-2022-20737

Cisco Adaptive Security Appliance Software Clientless SSL VPN Heap Overflow Vulnerability

8.5 High

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.

Attack profile

How easy it is to exploit

Attack vector
Network
Complexity
Low
Privileges needed
Low
User interaction
None

What an attacker can affect

Confidentiality
Low
Integrity
None
Availability
High

Exploit likelihood

1.18%Up 0.1 points since May 3, 2022
90%50%10%1%

What each source reports

CVE List Score used 8.5

Cisco Adaptive Security Appliance Software Clientless SSL VPN Heap Overflow Vulnerability

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.

Record
CVE-2022-20737
CVSS 3.1
8.5 HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:H
Weakness
CWE-122
Updated
2026-11-02
EUVDEUVD-2022-25987 8.5

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.

Record
EUVD-2022-25987
CVSS 3.1
8.5 HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:H
Updated
2026-11-03
GitHub AdvisoriesGHSA-m263-3fx7-gm9v 7.1

A vulnerability in the handler for HTTP authentication for resources accessed through the...

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.

Record
GHSA-m263-3fx7-gm9v
CVSS 3.1
7.1 HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H
Weakness
CWE-787
Updated
2026-11-02
NVD 8.5

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.

Record
CVE-2022-20737
CVSS 3.1
8.5 HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:H
CVSS 3.1
7.1 HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H
CVSS 2.0
7.0 HighAV:N/AC:M/Au:S/C:P/I:N/A:C
Weakness
CWE-122, CWE-787
Updated
2026-11-02

Affected products

History

History
RecordedChangedSources
aliases, publishedEUVD
first indexedCVE List, GitHub Advisories, NVD

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2022-20737 is a high vulnerability (CVSS 8.5) in Cisco Adaptive Security Appliance Software, published May 3, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.18%, the 67th percentile. No source names a fixed version.

References

MoveEnter Open