CVE-2019-1855: Cisco Jabber for Windows DLL Preloading Vulnerability

Severity: high (CVSS 7.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-07-04 · updated 2026-06-17
Weakness: CWE-264

Description

A vulnerability in the loading mechanism of specific dynamic link libraries in Cisco Jabber for Windows could allow an authenticated, local attacker to perform a DLL preloading attack. To exploit this vulnerability, the attacker would need to have valid credentials on the Windows system. The vulnerability is due to insufficient validation of the resources loaded by the application at run time. An attacker could exploit this vulnerability by crafting a malicious DLL file and placing it in a specific location on the targeted system. The malicious DLL file would execute when the Jabber application launches. A successful exploit could allow the attacker to execute arbitrary code on the target machine with the privileges of another user's account.

Affected products

Cisco Jabber: before 12.6\(2\) — fixed in 12.6\(2\)

How to fix

Upgrade to a fixed version: Cisco Jabber 12.6\(2\). Check the vendor advisory for mitigations.

References

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