CVE-2026-12986: A critical vulnerability in Admin GUI in Payara Server Full 4.x, 5.x, 6.x, 7.x, 7.2026.x, 6.2025.x, 6.2024.x on All platforms that allows the attacker to leak t

A critical vulnerability in Admin GUI in Payara Server Full 4.x, 5.x, 6.x, 7.x, 7.2026.x, 6.2025.x, 6.2024.x on All platforms that allows the attacker to leak t

A critical vulnerability in Admin GUI in Payara Server Full 4.x, 5.x, 6.x, 7.x, 7.2026.x, 6.2025.x, 6.2024.x on All platforms that allows the attacker to leak the admin gfresttoken to an attacker-controlled host that can result in a full unauthenticated takeover of Payara admin domain. A Server-Side Request Forgery (SSRF) vulnerability in the DownloadServlet of the Admin GUI in Payara Server allows a remote attacker to exfiltrate the administrator's REST session token (gfresttoken) to an attacker-controlled host via a crafted request URL. Combined with the absence of CSRF protection on DownloadServlet, an unauthenticated attacker can trick a logged-in administrator into triggering the token leak, then replay the stolen token to gain full administrative access to the Payara domain, leading to arbitrary code execution via WAR deployment. The vulnerability exists in the DownloadServlet and associated ContentSource implementations (LogViewerContentSource, LogFilesContentSource, LBConfigContentSource, ClientStubsContentSource) within the admingui:console-common module.

Description from the National Vulnerability Database, published by 769c9ae7-73c3-4e47-ae19-903170fc3eb8

What it means for a small business

If your business uses Payara Server, install the vendor's update. If you're not sure whether you use it, ask whoever manages your computers.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.27%, higher than 19% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 29, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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