Description
A stored cross-site scripting (XSS) vulnerability exists in osTicket 1.18.3 due to improper sanitization of the thread entry title field. User-controlled input in the title is stored without adequate HTML escaping and later rendered in multiple staff-facing templates without proper output encoding. An attacker can inject arbitrary JavaScript by submitting a crafted ticket reply or email with a malicious subject line.
References5
- github.com/fr3akhacks/cve-disclosures/blob/master/osTicket/CVE-…
- github.com/osTicket/osTicket/blob/v1.18.3/include/staff/templat…
- github.com/osTicket/osTicket/blob/v1.18.3/include/staff/templat…
- github.com/osTicket/osTicket/blob/v1.18.3/include/staff/templat…
- github.com/osTicket/osTicket/commit/1e39bf1cf78fa298285f19b98f6…
Metrics
- CVSS 3.1
-
6.1
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 28 · as of 13 November 2026
- CWE
- CWE-79
Could this be exploited in your environment?
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