CVE-2026-2587: GlassFish's gadget handler is vulnerable to RCE

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
• EPSS 0.7%, percentile 51: FIRST’s model estimates a 0.7% chance of exploitation activity in the next 30 days, higher than 51% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
• Needs a user to click or open something. Phishing makes that realistic, but it is not wormable.
• Only applies if your dependency tree includes org.glassfish.main.admingui:admingui (Maven) < 8.0.2, fixed in 8.0.2; org.glassfish.jsftemplating:jsftemplating (Maven) < 4.2.0, fixed in 4.2.0. Check your lockfile, including transitive dependencies.

What it is

A critical Remote Code Execution (RCE) vulnerability was identified in the server-side template rendering mechanism used by the Glassfish gadget handler. The application processes .xml files and evaluates user-supplied values within a context where Expression Language (EL) “expressions” are processed without proper sanitization or escaping. By injecting expressions such as #{77}, the server returns 49, confirming server-side EL evaluation. This issue allows a remote attacker to fully compromise the underlying host, enabling capabilities as reading/modifying data, executing arbitrary commands, persistence, and lateral movement. This issue affects Eclipse GlassFish: from 8.0.0 to 8.0.1, fixed in 8.0.2; 7.1.0, fixed in 7.1.1; from 7.0.0 to 7.0.25, fixed in 7.0.26. Impact on versions from 5.1.0 to 6.2.5 is unknown.

From the GitHub advisory

A critical Remote Code Execution (RCE) vulnerability was identified in the server-side template rendering mechanism used by the Glassfish gadget handler. The application processes .xml files and evaluates user-supplied values within a context where Expression Language (EL) “expressions” are processed without proper sanitization or escaping. By injecting expressions such as #{77}, the server returns 49, confirming server-side EL evaluation. This issue allows a remote attacker to fully compromise the underlying host, enabling capabilities as reading/modifying data, executing arbitrary commands, persistence, and lateral movement.

Weakness type: CWE-917.

Product: org.glassfish.main.admingui:admingui (Maven) · Assigned by: eclipse · Published: 2026-05-19

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: none (no login)
• User interaction: required (a user must click/open something)
• Scope: changed (can affect other components)

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation none, automatable no, technical impact total.
• FIRST EPSS (model of 2026-10-21): 0.67% probability of exploitation activity in the next 30 days; percentile 51.

Timeline

• 2026-05-19 — CVE record published by eclipse
• 2026-05-19 — GitHub-reviewed advisory GHSA-29wv-cv7p-xjc2 published (critical)
• 2026-06-29 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-29wv-cv7p-xjc2 github.com
2. CVE.org record CVE-2026-2587 cve.org
3. NVD entry CVE-2026-2587 nvd.nist.gov

Other references from the CVE record and advisory

1. gitlab.eclipse.org gitlab.eclipse.org
2. github.com github.com

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