CVE-2025-20183

MEDIUM
Published Feb 5, 2025 Modified Aug 5, 2025 CWE-20

Description

A vulnerability in a policy-based Cisco Application Visibility and Control (AVC) implementation of Cisco AsyncOS Software for Cisco Secure Web Appliance could allow an unauthenticated, remote attacker to evade the antivirus scanner and download a malicious file onto an endpoint.  The vulnerability is due to improper handling of a crafted range request header. An attacker could exploit this vulnerability by sending an HTTP request with a crafted range request header through the affected device. A successful exploit could allow the attacker to evade the antivirus scanner and download malware onto the endpoint without detection by Cisco Secure Web Appliance.

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CVSS v3.1 Score

5.8
MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N

Weakness Type (CWE)

CWE-20 Improper Input Validation

Affected Products

Vendor Product
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco asyncos
cisco secure_web_appliance_virtual_s1000v
cisco secure_web_appliance_virtual_s100v
cisco secure_web_appliance_virtual_s300v
cisco secure_web_appliance_virtual_s600v
cisco secure_web_appliance_s196
cisco secure_web_appliance_s396
cisco secure_web_appliance_s696

References

Frequently Asked Questions

What is CVE-2025-20183? +
A vulnerability in a policy-based Cisco Application Visibility and Control (AVC) implementation of Cisco AsyncOS Software for Cisco Secure Web Appliance could allow an unauthenticated, remote attacker to evade the antivirus scanner and download a malicious file onto an endpoint.  The vulnerability is due to improper handling of a crafted range request header. An attacker could exploit this vulnerability by sending an HTTP request with a crafted range request header through the affected device. A successful exploit could allow the attacker to evade the antivirus scanner and download malware onto the endpoint without detection by Cisco Secure Web Appliance. It has a CVSS v3.1 base score of 5.8 (MEDIUM).
How severe is CVE-2025-20183? +
CVE-2025-20183 has a CVSS v3.1 score of 5.8 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.
What products are affected by CVE-2025-20183? +
CVE-2025-20183 affects products from cisco, specifically: asyncos, secure_web_appliance_s196, secure_web_appliance_s396, secure_web_appliance_s696, secure_web_appliance_virtual_s1000v, secure_web_appliance_virtual_s100v, secure_web_appliance_virtual_s300v, secure_web_appliance_virtual_s600v. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2025-20183? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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