Content-filter bypass via trusted TLS SNI
Published Apr 21, 2022 · Updated Nov 6, 2024
Policy bypass in Cisco Umbrella Secure Web Gateway allows remote authenticated users to evade TLS decryption with a crafted request. The automatic decryption function trusts the TLS SNI extension to identify the destination domain and decide whether to decrypt an HTTPS request. An authenticated user able to send TLS traffic from an adjacent client can evade content filtering and download malicious content to a protected host.
Summary
What happened
Policy bypass in Cisco Umbrella Secure Web Gateway allows remote authenticated users to evade TLS decryption with a crafted request. The automatic decryption function trusts the TLS SNI extension to identify the destination domain and decide whether to decrypt an HTTPS request. An authenticated user able to send TLS traffic from an adjacent client can evade content filtering and download malicious content to a protected host.
The record
- CVE
- CVE-2022-20805
- Published
- Apr 21, 2022
- Updated
- Nov 6, 2024
- Vendor
- ClamAV
- Product
- Cisco Umbrella Insights Virtual Appliance
- Classifications
- CWE-693, T1573
- Attack vector
- adjacent
- Privileges
- authenticated
Timeline
How it unfolded
- Apr 21, 2022CVE publishedPublication date reported by the CVE source.
- Nov 6, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=n/a
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
Your stack
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Your stack
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