Vulnerability · Published Jun 16, 2026 · Assigned by INCIBE

CVE-2026-9507Session fixation vulnerability in Enhancesoft's osTicket

Medium 5.1

In plain English

A medium-severity security flaw in osTicket from Enhancesoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 35% of all known vulnerabilities).

Severity (CVSS 4.0)5.1Medium

Exploit odds (30 days)0.4%top 65.2% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

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.

Affected products (as reported)

Vendor	Product	Versions
Enhancesoft	osTicket	1.18.2

Weakness: CWE-38 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

References

https://www.incibe.es/en/incibe-cert/notices/aviso/session-fixation-vulnerability-enhancesofts-osticket patch