CVE-2017-9506 in OAuth Plugin
Summary
by MITRE
The IconUriServlet of the Atlassian OAuth Plugin from version 1.3.0 before version 1.9.12 and from version 2.0.0 before version 2.0.4 allows remote attackers to access the content of internal network resources and/or perform an XSS attack via Server Side Request Forgery (SSRF).
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Analysis
by VulDB Data Team • 11/10/2019
The CVE-2017-9506 vulnerability resides within the IconUriServlet component of Atlassian's OAuth Plugin, representing a critical server-side request forgery flaw that enables remote attackers to bypass network security controls. This vulnerability affects versions prior to 1.9.12 in the 1.3.0-1.9.12 release line and versions prior to 2.0.4 in the 2.0.0-2.0.4 release line, creating a substantial attack surface for malicious actors targeting Atlassian products. The flaw specifically manifests through the IconUriServlet's improper handling of user-supplied URI parameters, allowing attackers to construct malicious requests that can traverse internal network boundaries.
The technical exploitation of this vulnerability occurs through a server-side request forgery mechanism where the OAuth plugin's servlet fails to properly validate or sanitize incoming URI parameters. When an attacker crafts a malicious request containing a URI that points to internal network resources, the servlet processes this request without adequate authorization checks, effectively allowing the vulnerable system to make outbound connections to internal services that would normally be restricted. This behavior directly maps to CWE-918, which defines server-side request forgery vulnerabilities where applications fail to validate or properly sanitize user input that influences HTTP requests.
The operational impact of this vulnerability extends beyond simple information disclosure, as it enables attackers to perform cross-site scripting attacks through the same exploitation vector. When combined with the SSRF capabilities, attackers can potentially access internal network resources that contain sensitive data or system information, while simultaneously executing malicious scripts against users who interact with the vulnerable application. This dual threat capability makes the vulnerability particularly dangerous in enterprise environments where Atlassian products are commonly deployed.
Security practitioners should note that this vulnerability aligns with ATT&CK technique T1190, which describes the exploitation of vulnerabilities in web applications to perform server-side request forgery attacks. The attack chain typically involves initial reconnaissance to identify vulnerable Atlassian installations, followed by crafting of malicious payloads that leverage the IconUriServlet's trust model to access internal resources. The vulnerability's impact is amplified in environments where internal network services lack proper authentication mechanisms or where the vulnerable application has elevated privileges within the network infrastructure.
Organizations should implement immediate mitigations including upgrading to patched versions of the Atlassian OAuth Plugin, implementing network segmentation to restrict outbound connections from the vulnerable application, and deploying web application firewalls that can detect and block suspicious URI patterns. The remediation process must also include thorough network access control reviews to ensure that internal services are not inadvertently exposed through this vulnerability. Additionally, security monitoring should be enhanced to detect unusual outbound connection patterns that may indicate exploitation attempts, particularly targeting internal resources that should not be accessible from external networks.