CVE-2022-20805

MEDIUM

Cisco Umbrella Secure Web Gateway - Authenticated SSL Decryption Bypass via TLS SNI Extension

Title source: llm
STIX 2.1

Description

A vulnerability in the automatic decryption process in Cisco Umbrella Secure Web Gateway (SWG) could allow an authenticated, adjacent attacker to bypass the SSL decryption and content filtering policies on an affected system. This vulnerability is due to how the decryption function uses the TLS Sever Name Indication (SNI) extension of an HTTP request to discover the destination domain and determine if the request needs to be decrypted. An attacker could exploit this vulnerability by sending a crafted request over TLS from a client to an unknown or controlled URL. A successful exploit could allow an attacker to bypass the decryption process of Cisco Umbrella SWG and allow malicious content to be downloaded to a host on a protected network. There are workarounds that address this vulnerability.

References (1)

Core 1
Core References

Scores

CVSS v3 4.1
EPSS 0.0003
EPSS Percentile 10.3%
Attack Vector ADJACENT_NETWORK
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-327 CWE-693
Status published
Products (1)
cisco/umbrella_secure_web_gateway
Published Apr 21, 2022
Tracked Since Feb 18, 2026