CVE-2026-9507 Session fixation vulnerability in Enhancesoft's osTicket
Attackers can hijack user accounts in osTicket by maintaining a pre-authentication session ID after the victim logs in.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-9507?
CVE-2026-9507 is a medium-severity authentication bypass vulnerability in Enhancesoft osTicket, published on 16 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
A session fixation vulnerability has been identified in osTicket v1.18.2. This security flaw allows an attacker to hijack a victim’s account by keeping the initial session identifier (OSTSESSID) active after a successful login.
The issue lies in the fact that the application does not invalidate the pre-authentication cookie or generate a new identifier for the authenticated context. As a result, if an attacker manages to set a known session identifier in the victim’s browser, they will be able to maintain unauthorised access to the account once the victim has authenticated.
Weakness: CWE-38
Which versions are affected by CVE-2026-9507?
How do I fix CVE-2026-9507?
No fix has been published for CVE-2026-9507 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-9507 being exploited?
There is no known exploitation of CVE-2026-9507 in the wild and no public exploit code.
Sources
Also known as GHSA-6cj6-2fg2-2r4g.