CVE-2021-25925 is a Stored Cross-Site Scripting (XSS) vulnerability affecting SiCKRAGE versions 4.2.0 through 10.0.11.dev1. SiCKRAGE is an application used for managing and automating TV show downloads. The vulnerability arises because user input is not properly validated or sanitized on the server side before being stored and subsequently rendered in the web interface. This flaw allows an attacker to inject arbitrary JavaScript code that is persistently stored and executed in the context of other users’ browsers when they access the affected pages. The vulnerability is classified under CWE-79, which pertains to improper neutralization of input during web page generation. Exploitation requires the attacker to have at least limited privileges (PR:L) and some user interaction (UI:R), such as convincing a user to visit a maliciously crafted page or link. The CVSS v3.1 base score is 5.4 (medium severity), reflecting that the attack vector is network-based (AV:N), with low attack complexity (AC:L), requiring privileges and user interaction, and impacting confidentiality and integrity to a limited extent, but not availability. While no known exploits have been reported in the wild, the vulnerability could allow attackers to steal sensitive information such as session cookies or perform actions on behalf of authenticated users, potentially leading to account compromise or further attacks within the application environment. No official patches or fixes are linked in the provided data, indicating that mitigation may require manual intervention or updates from the software maintainers.

For European organizations using SiCKRAGE, this vulnerability poses a risk primarily to confidentiality and integrity of user data. Attackers exploiting this XSS flaw could hijack user sessions, steal authentication tokens, or manipulate displayed content, potentially leading to unauthorized access or data leakage. Although SiCKRAGE is typically used in personal or small-scale environments, organizations that integrate it into media management or internal services could face reputational damage or operational disruption. The medium severity score suggests a moderate risk, but the impact could escalate if attackers leverage the vulnerability as a foothold for lateral movement or privilege escalation within a network. Since exploitation requires some level of user interaction and privileges, the threat is somewhat mitigated by user awareness and access controls. However, in environments where SiCKRAGE is exposed to broader user bases or external networks, the risk increases. European entities with less mature cybersecurity practices or those running outdated versions are particularly vulnerable. Additionally, the lack of known exploits in the wild does not preclude future attacks, especially as threat actors often weaponize such vulnerabilities once publicly disclosed.

1. Immediate upgrade: Organizations should upgrade SiCKRAGE to a version beyond 10.0.11.dev1 once an official patch is released. If no patch is available, consider disabling or restricting access to the application until remediation is possible. 2. Input validation and sanitization: Implement or enforce strict server-side input validation and output encoding to neutralize potentially malicious scripts. 3. Access controls: Limit SiCKRAGE access to trusted users only, ideally within internal networks or via VPN, to reduce exposure. 4. Web Application Firewall (WAF): Deploy a WAF with rules to detect and block common XSS payloads targeting SiCKRAGE endpoints. 5. User awareness: Educate users about the risks of clicking untrusted links or interacting with suspicious content within the application. 6. Monitoring and logging: Enable detailed logging of user inputs and application errors to detect potential exploitation attempts. 7. Segmentation: Isolate SiCKRAGE servers from critical infrastructure to minimize impact if compromised. 8. Regular audits: Conduct periodic security assessments and code reviews focusing on input handling in SiCKRAGE or similar applications.