Eclipse Glassfish: Improper Neutralization of Special Elements used in an Expression Language Statement
CVE-2026-2587 is a critical-severity improper neutralization of special elements used in an expression language statement vulnerability in Eclipse Glassfish from Eclipse Foundation, with a CVSS 3.1 base score of 9.6 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. The record lists versions 7.0.26, 7.1.1, 8.0.2 as the first without the flaw, so updating Eclipse Glassfish to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.65% chance of exploitation within 30 days, higher than 52% of scored CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update Eclipse Glassfish to 7.0.26 or 7.1.1 or 8.0.2, whichever matches your release line, or a later version.
- Update Glassfish to 8.0.2 or a later version.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Eclipse Foundation | Eclipse Glassfish | 7.0.0 up to, but not including, 7.0.26; 7.1.0 up to, but not including, 7.1.1; 8.0.0 up to, but not including, 8.0.2 | 7.0.26, 7.1.1, 8.0.2 |
| Eclipse | Glassfish | before 8.0.2 | 8.0.2 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H. Scored by CNA (eclipse.org).
Official description
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 #{7*7}, 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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Neutralization of Special Elements used in an Expression Language Statement
The product constructs all or part of an expression language (EL) statement in a framework such as a Java Server Page (JSP) using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended EL statement before it is executed.
How developers prevent this class of flaw
- Avoid adding user-controlled data into an expression interpreter when possible.
- If user-controlled data must be added to an expression interpreter, one or more of the following should be performed: Validate that the user input will not evaluate as an expression Encode the user input in a way that ensures it is not evaluated as an expression
- The framework or tooling might allow the developer to disable or deactivate the processing of EL expressions, such as setting the isELIgnored attribute for a JSP page to true.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Technical write-ups (may include proof of concept)
- gitlab.eclipse.org/security/cve-assignment/-/issues/86Exploit, Issue Tracking, Third Party Advisory
Other vulnerabilities in Eclipse Glassfish
- 9.6 Critical severity
- 9.1 Critical severity
- 9.8 Critical severity
- 9.8 Critical severity
- 7.5 High severity
Recent Improper Neutralization of Special Elements used in an Expression Language Statement vulnerabilities
- 9.0 Critical severity
- 8.6 High severity
- 8.1 High severity
- 9.0 Critical severity
- 9.0 Critical severity
- 9.8 Critical severity
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