CVE-2026-9507
MediumCVSS 5.1Summary
A session fixation vulnerability has been identified in osTicket v1.18.2, allowing an attacker to hijack a victim’s account by keeping the initial session identifier (OSTSESSID) active after a successful login.
Risk Assessment
This vulnerability poses a risk of unauthorized access to user accounts, potentially leading to data theft or other malicious activities.
Recommendation
It is recommended to update to the latest version of osTicket that addresses this vulnerability and to implement mechanisms to invalidate cookies prior to authentication.
Other vulnerabilities in osTicket v1.18.2
See all- CVE-2026-38447Critical
osTicket 1.18.3 generates API keys using a predictable construction based on MD5 hashing with low-entropy inputs like timestamp and client IP. This allows an attacker to brute-force the key within a feasible time window.
- CVE-2026-18363Critical
In osTicket versions prior to 1.17.8 and 1.18.4, a logic flaw in password reset token validation causes the expiry check to be performed only when the timestamp lookup fails, allowing reuse of a valid token.
- CVE-2026-22200High
A vulnerability in osTicket versions 1.18.x prior to 1.18.3 and 1.17.x prior to 1.17.7 allows a remote attacker to read arbitrary files from the server via ticket PDF export. The attacker can submit a ticket containing crafted rich-text HTML with PHP filter expressions that are insufficiently sanitized before being processed by the mPDF PDF generator. When the ticket is exported to PDF, the generated file can embed contents of attacker-selected files from the server filesystem as bitmap images, leading to disclosure of sensitive local files in the context of the osTicket application user.
- CVE-2020-24881Critical
SSRF vulnerability in osTicket before version 1.14.3 allows an attacker to add a malicious file to the server or perform port scanning.
- CVE-2019-14750Medium
In osTicket before version 1.10.7 and versions 1.12.x before 1.12.1, a stored XSS vulnerability was discovered in setup/install.php. Lack of input sanitization in the firstname and lastname fields allows injection of malicious queries that are then executed.
- CVE-2019-14749High
An issue was discovered in osTicket before 1.10.7 and 1.12.x before 1.12.1 where CSV formula injection exists in the export spreadsheets functionality. Spreadsheets are generated dynamically from unvalidated user input in the Name and Internal Notes fields in the Users tab, and the Issue Summary field in the tickets tab. This allows agents to download data in .csv or .xls format that may contain malicious formulas.
- CVE-2019-11537Medium
In osTicket before version 1.12, an XSS vulnerability exists via uploading a crafted CSV file to the User Importer. File contents can appear in an error message, allowing script execution in the browser. This can lead to local file inclusion.
- CVE-2017-15580Critical
osTicket version 1.10.1 allows uploading 'html' files but does not properly validate the contents of the uploaded files, enabling the upload of arbitrary file types, including malicious ones. An attacker can exploit this vulnerability to upload malicious files to the web application.
- CVE-2017-14396Critical
In osTicket before 1.10.1, SQL injection is possible by constructing an array via use of square brackets at the end of a parameter name, as demonstrated by the key parameter to file.php.
- CVE-2009-2361High
SQL injection vulnerability in include/class.staff.php in osTicket before 1.6 RC5. Remote attackers can execute arbitrary SQL commands via the staff username parameter.
Original NVD description (English source)
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.

