Secure Email and Web
CVE-2022-20952: A vulnerability in the scanning engines of Cisco AsyncOS Software for Cisco Secure Web Appliance, formerly…
A vulnerability in the scanning engines of Cisco AsyncOS Software for Cisco Secure Web Appliance, formerly known as Cisco Web Security Appliance (WSA), could allow an unauthenticated, remote attacker to bypass a configured rule, thereby allowing traffic onto a network that should have been blocked.
Published
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| Cisco Secure Web Appliance 11.8 | See the advisory |
| Cisco Secure Web Appliance 11.8 | See the advisory |
| Cisco Secure Web Appliance 11.8 | See the advisory |
| Cisco Secure Web Appliance 11.8 | See the advisory |
| Cisco Secure Web Appliance 12.0 | See the advisory |
| Cisco Secure Web Appliance 12.0 | See the advisory |
| Cisco Secure Web Appliance 12.5 | See the advisory |
| Cisco Secure Web Appliance 12.5 | See the advisory |
| Cisco Secure Web Appliance 12.5 | See the advisory |
| Cisco Secure Web Appliance 12.5 | See the advisory |
| Cisco Secure Web Appliance 14.5 | See the advisory |
| Cisco Secure Web Appliance 14.0 | See the advisory |
| Cisco Secure Web Appliance 14.0 | See the advisory |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
A vulnerability in the scanning engines of Cisco AsyncOS Software for Cisco Secure Web Appliance, formerly known as Cisco Web Security Appliance (WSA), could allow an unauthenticated, remote attacker to bypass a configured rule, thereby allowing traffic onto a network that should have been blocked. This vulnerability exists because malformed, encoded traffic is not properly detected. An attacker could exploit this vulnerability by connecting through an affected device to a malicious server and receiving malformed HTTP responses. A successful exploit could allow the attacker to bypass an explicit block rule and receive traffic that should have been rejected by the device.
Exploitation
The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerabilities that are described in this advisory.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 11 Oct 2026.