Cisco
CVE-2026-20056
MEDIUM
Severity by source
AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N
Lifecycle Timeline
2DescriptionCVE.org
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.
AnalysisAI
Cisco Secure Web Appliance's DVS Engine improperly handles certain archive files, allowing unauthenticated remote attackers to bypass the anti-malware scanner and deliver malicious archives to end users. An attacker can exploit this by sending crafted archive files through affected devices to circumvent malware detection. While downloaded malware requires manual extraction and execution by the user, this vulnerability enables distribution of malicious content that would normally be blocked.
Technical ContextAI
Classified as CWE-494 (Download of Code Without Integrity Check). 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 exp
Affected ProductsAI
A vulnerability in the Dynamic Vectoring and Streaming (DVS) Engine implementation of Cisco AsyncOS Software for Cisco Secure Web Appliance could allo
RemediationAI
Monitor vendor advisories for a patch. Restrict network access to the affected service where possible.
Same weakness CWE-494 – Download of Code Without Integrity Check
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External POC / Exploit Code
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