CVE-2020-3537: Cisco Jabber for Windows Universal Naming Convention Link Handling Vulnerability

Severity: medium (CVSS 5.7 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-09-04 · updated 2026-06-17
Weakness: CWE-200

Description

A vulnerability in Cisco Jabber for Windows software could allow an authenticated, remote attacker to gain access to sensitive information. The vulnerability is due to improper validation of message contents. An attacker could exploit this vulnerability by sending specially crafted messages that contain Universal Naming Convention (UNC) links to a targeted user and convincing the user to follow the provided link. A successful exploit could allow the attacker to cause the application to access a remote system, possibly allowing the attacker to gain access to sensitive information that the attacker could use in additional attacks.

Affected products

Cisco Jabber: from 12.1 before 12.1.3; from 12.5 before 12.5.2; from 12.6 before 12.6.3; from 12.7 before 12.7.2; from 12.8 before 12.8.3; from 12.9 before 12.9.1 — fixed in 12.1.3, 12.5.2, 12.6.3, 12.7.2, 12.8.3, 12.9.1

How to fix

Upgrade to a fixed version: Cisco Jabber 12.1.3, 12.5.2, 12.6.3, 12.7.2. Check the vendor advisory for mitigations.

References

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