CVE-2026-20056
Cisco Secure Web Appliance TBD Bypass Vulnerability
A vulnerability in the Dynamic Vectoring and Streaming (DVS) Engine implementation of Cisco AsyncOS Software for Cisco Secure Web Appliance could allow an unauthenticated, remote attacker to bypass the anti-malware scanner, allowing malicious archive files to be downloaded.
This vulnerability is due to improper handling of certain archive files. An attacker could exploit this vulnerability by sending a crafted archive file, which should be blocked, through an affected device. A successful exploit could allow the attacker to bypass the anti-malware scanner and download malware onto an end user workstation. The downloaded malware will not automatically execute unless the end user extracts and launches the malicious file.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used 4.0
Cisco Secure Web Appliance TBD Bypass Vulnerability
A vulnerability in the Dynamic Vectoring and Streaming (DVS) Engine implementation of Cisco AsyncOS Software for Cisco Secure Web Appliance could allow an unauthenticated, remote attacker to bypass the anti-malware scanner, allowing malicious archive files to be downloaded.
This vulnerability is due to improper handling of certain archive files. An attacker could exploit this vulnerability by sending a crafted archive file, which should be blocked, through an affected device. A successful exploit could allow the attacker to bypass the anti-malware scanner and download malware onto an end user workstation. The downloaded malware will not automatically execute unless the end user extracts and launches the malicious file.
- Record
CVE-2026-20056- CVSS 3.1
- 4.0 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N - Weakness
- CWE-494
- Updated
- 2026-11-02
EUVDEUVD-2026-5425 4.0
A vulnerability in the Dynamic Vectoring and Streaming (DVS) Engine implementation of Cisco AsyncOS Software for Cisco Secure Web Appliance could allow an unauthenticated, remote attacker to bypass the anti-malware scanner, allowing malicious archive files to be downloaded.
This vulnerability is due to improper handling of certain archive files. An attacker could exploit this vulnerability by sending a crafted archive file, which should be blocked, through an affected device. A successful exploit could allow the attacker to bypass the anti-malware scanner and download malware onto an end user workstation. The downloaded malware will not automatically execute unless the end user extracts and launches the malicious file.
- Record
EUVD-2026-5425- CVSS 3.1
- 4.0 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-5v8r-9wmj-294x 4.0
A vulnerability in the Dynamic Vectoring and Streaming (DVS) Engine implementation of Cisco...
A vulnerability in the Dynamic Vectoring and Streaming (DVS) Engine implementation of Cisco AsyncOS Software for Cisco Secure Web Appliance could allow an unauthenticated, remote attacker to bypass the anti-malware scanner, allowing malicious archive files to be downloaded.
This vulnerability is due to improper handling of certain archive files. An attacker could exploit this vulnerability by sending a crafted archive file, which should be blocked, through an affected device. A successful exploit could allow the attacker to bypass the anti-malware scanner and download malware onto an end user workstation. The downloaded malware will not automatically execute unless the end user extracts and launches the malicious file.
- Record
GHSA-5v8r-9wmj-294x- CVSS 3.1
- 4.0 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N - Weakness
- CWE-494
- Updated
- 2026-11-02
NVD 4.0
A vulnerability in the Dynamic Vectoring and Streaming (DVS) Engine implementation of Cisco AsyncOS Software for Cisco Secure Web Appliance could allow an unauthenticated, remote attacker to bypass the anti-malware scanner, allowing malicious archive files to be downloaded.
This vulnerability is due to improper handling of certain archive files. An attacker could exploit this vulnerability by sending a crafted archive file, which should be blocked, through an affected device. A successful exploit could allow the attacker to bypass the anti-malware scanner and download malware onto an end user workstation. The downloaded malware will not automatically execute unless the end user extracts and launches the malicious file.
- Record
CVE-2026-20056- CVSS 3.1
- 4.0 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N - Weakness
- CWE-494
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-20056 is a medium vulnerability (CVSS 4.0) in Cisco Secure Web Appliance, published February 4, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.17%, the 5th percentile. No source names a fixed version.