SB2026020566 - Antimalware protection bypass in Cisco AsyncOS for Secure Web Appliance
Published: February 5, 2026
Security Bulletin ID
SB2026020566
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Data manipulation
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Download of code without integrity check (CVE-ID: CVE-2026-20056)
CWE-ID: CWE-494 - Download of Code Without Integrity Check
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to bypass implemented security restrictions.
The vulnerability exists due to software does not perform software integrity check in the Dynamic Vectoring and Streaming (DVS) Engine implementation. A remote attacker can use a specially crafted archive to bypass antimalware scanner and download malware onto an end user workstation.
Remediation
Install update from vendor's website.