<!-- Note that this issue is configured (see the quick actions at the bottom) to be created as confidential. Note that a vulnerability does not need to actually be resolved before it is reported and that these reports can be revised as needed (reopen the issue to request changes). If you do not know how to fill certain fields, mark that in the comment and we will help you. You can delete the comments (or not). --> <!-- Required. Specify the project's name (e.g., "Eclipse Dash") and Eclipse Foundation ID, e.g., "technology.dash". --> ## Basic information **Project name:** Glassfish ## What are the affected versions? 7.0.15 ## Details of the issue Summary: In Eclipse GlassFish version 7.0.15 is possible to perform Reflected Cross-site scripting attacks. Reflected cross-site scripting vulnerabilities arise when data is copied from a request and echoed into the application's immediate response in an unsafe way. An attacker can use the vulnerability to construct a request that, if issued by another application user, will cause JavaScript code supplied by the attacker to execute within the user's browser in the context of that user's session with the application. • Prerequisites: The victim must be authenticated within the Administration Console. Step-by-step instructions and PoC An unauthenticated remote attacker can create a malicious link that, if it is delivered to the victim (e.g., phishing), can cause JavaScript code execution in the victim's browser and supply some information to the attacker or run arbitrary HTTP Request in the context of victim's session. Affected Endpoints • URL: https://[IP]:[PORT]/shared/instanceStatus.jsf • HTTP GET Parameter: instanceName Below there is the evidence with the vulnerability details and the payloads used. Payload used to exploit the vulnerability: https://[IP]:[PORT]/shared/instanceStatus.jsf?instanceName=%22%20id=%22x%22%2 0tabindex=%221%22%20onfocus=%22alert(1)%22%20autofocus=%22 Security Impact An attacker can exploit this vulnerability to extract some information or run arbitrary HTTP Request in the context of victim's session. Remediation Steps In most situations where user-controllable data is copied into application responses, cross-site scripting attacks can be prevented using two layers of defences: - Input should be validated as strictly as possible on arrival, given the kind of content that it is expected to contain. For example, personal names should consist of alphabetical and a small range of typographical characters, and be relatively short; a year of birth should consist of exactly four numerals; email addresses should match a well-defined regular expression. Input which fails the validation should be rejected, not sanitized. - User input should be HTML-encoded at any point where it is copied into application responses. All HTML metacharacters, including < > " ' and =, should be replaced with the corresponding HTML entities (&lt; &gt; etc). In cases where the application's functionality allows users to author content using a restricted subset of HTML tags and attributes (for example, blog comments which allow limited formatting and linking), it is necessary to parse the supplied HTML to validate that it does not use any dangerous syntax; this is a non-trivial task. (How one can reproduce the issue - this is very important) <!-- Please, do not remove the line below. It will create a confidential issue that will be visible only to you and the members of this project. Confidential issues are used to keep security vulnerabilities private until they are sorted out. Eclipse Projects follow Responsible Disclosure best practices: the initial report is made privately, but with the full details being published once a patch has been made available (sometimes with a delay to allow more time for the patches to be installed). -->