CVE-2020-3482: Cisco Expressway Software Unauthorized Access Information Disclosure Vulnerability

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-11-18 · updated 2026-06-17
Weakness: CWE-284

Description

A vulnerability in the Traversal Using Relays around NAT (TURN) server component of Cisco Expressway software could allow an unauthenticated, remote attacker to bypass security controls and send network traffic to restricted destinations. The vulnerability is due to improper validation of specific connection information by the TURN server within the affected software. An attacker could exploit this issue by sending specially crafted network traffic to the affected software. A successful exploit could allow the attacker to send traffic through the affected software to destinations beyond the application, possibly allowing the attacker to gain unauthorized network access.

Affected products

Cisco Expressway: before x12.6.3 — fixed in x12.6.3
Cisco TelePresence Video Communication Server (VCS) Expressway: before x12.6.3 — fixed in x12.6.3

How to fix

Upgrade to a fixed version: Cisco Expressway x12.6.3; Cisco TelePresence Video Communication Server (VCS) Expressway x12.6.3. Check the vendor advisory for mitigations.

References

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