CVE-2026-21770 HCL Traveler for Microsoft Outlook (HTMO) is susceptible to DLL hijacking
An attacker can execute arbitrary code by exploiting a DLL hijacking vulnerability in HCL Traveler for Microsoft Outlook.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-21770?
CVE-2026-21770 is a medium-severity vulnerability in HCLSoftware HCL Traveler for Microsoft Outlook (HTMO), published on 17 Jul 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
HCL Traveler for Microsoft Outlook (HTMO) is susceptible to a DLL hijacking vulnerability which could allow an attacker to modify or replace the application with malicious content.
Weakness: CWE-427
Which versions are affected by CVE-2026-21770?
How do I fix CVE-2026-21770?
No fix has been published for CVE-2026-21770 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-21770 being exploited?
There is no known exploitation of CVE-2026-21770 in the wild and no public exploit code.
Sources
Also known as GHSA-7vgx-3mff-rjp8.