CVE-2026-15639 Reflected Cross-Site Scripting
Attackers can execute arbitrary JavaScript in victims' browsers via crafted links, potentially leading to session hijacking or data theft in Delinea Secret Server.
- 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-2026-15639?
CVE-2026-15639 is a critical cross-site scripting vulnerability in Delinea Secret Server (On-Prem), published on 15 Sep 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
An attacker can craft a malicious link that, if used by a legitimate user, may cause the user's browser to run JavaScript supplied by the attacker.
Weakness: CWE-79
Which versions are affected by CVE-2026-15639?
How do I fix CVE-2026-15639?
No fix has been published for CVE-2026-15639 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-15639 being exploited?
There is no known exploitation of CVE-2026-15639 in the wild and no public exploit code.
Sources
Also known as GHSA-5jwp-q2ph-6mgc.