CVE-2020-3430: Cisco Jabber for Windows Protocol Handler Command Injection Vulnerability

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.9% 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-78

Description

A vulnerability in the application protocol handling features of Cisco Jabber for Windows could allow an unauthenticated, remote attacker to execute arbitrary commands. The vulnerability is due to improper handling of input to the application protocol handlers. An attacker could exploit this vulnerability by convincing a user to click a link within a message sent by email or other messaging platform. A successful exploit could allow the attacker to execute arbitrary commands on a targeted system with the privileges of the user account that is running the Cisco Jabber client software.

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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