CVE-2026-59239 Stored XSS in Prospero Flow CRM email body allows administrator account takeover
A stored XSS vulnerability in Prospero Flow CRM allows attackers to execute arbitrary JavaScript and take over administrator accounts via unsanitized email bodies.
- 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-2026-59239?
CVE-2026-59239 is a high-severity cross-site scripting vulnerability in Roskus Prospero Flow CRM, published on 27 Jul 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
Stored Cross-site Scripting (CWE-79) in the email module in Roskus Prospero Flow CRM before 5.4.4 allows a remote, authenticated low-privileged user to execute arbitrary JavaScript in another user's browser, including administrators, leading to session compromise and account takeover, via a payload stored in an email body that is persisted without sanitization and rendered unescaped with {!! $email->body !!} when the recipient opens the message.
Weakness: CWE-79
Which versions are affected by CVE-2026-59239?
How do I fix CVE-2026-59239?
No fix has been published for CVE-2026-59239 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-2026-59239 being exploited?
There is no known exploitation of CVE-2026-59239 in the wild and no public exploit code.
Sources
Also known as GHSA-wpjv-rrg6-52x9.