CVE-2025-8554 in pybbs
Summary
by MITRE • 08/05/2025
A vulnerability, which was classified as problematic, has been found in atjiu pybbs up to 6.0.0. This issue affects some unknown processing of the file /admin/user/list. The manipulation of the argument Username leads to cross site scripting. The attack may be initiated remotely. The exploit has been disclosed to the public and may be used. The patch is named 2fe4a51afbce0068c291bc1818bbc8f7f3b01a22. It is recommended to apply a patch to fix this issue.
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Analysis
by VulDB Data Team • 09/03/2025
CVE-2025-8554 represents a cross site scripting vulnerability within the atjiu pybbs application version 6.0.0 and earlier, classified under CWE-79 as improper neutralization of input during web page generation. The vulnerability exists in the administrative user list functionality at the path /admin/user/list where the Username parameter is not properly sanitized or validated before being rendered in the web response. This flaw allows remote attackers to inject malicious scripts into the application's output through crafted Username inputs, potentially enabling session hijacking, credential theft, or defacement of the administrative interface. The vulnerability's exploitability is heightened by its remote attack vector, meaning malicious actors can trigger the XSS without requiring physical access or local network presence. The public disclosure of the exploit further increases the risk profile, as threat actors can readily leverage existing attack vectors. The patch referenced as 2fe4a51afbce0068c291bc1818bbc8f7f3b01a22 addresses the root cause by implementing proper input validation and output encoding mechanisms for the Username parameter. From an operational perspective, this vulnerability directly impacts the confidentiality, integrity, and availability of the administrative functions within the pybbs platform, potentially allowing unauthorized users to escalate privileges or compromise the entire system. The ATT&CK framework categorizes this vulnerability under T1059.008 for Command and Scripting Interpreter and T1566.001 for Spearphishing Attachment, as attackers could use the XSS to deliver additional malicious payloads or establish persistent access. Organizations should prioritize immediate patch deployment, implement web application firewalls to detect and block malicious input patterns, and conduct thorough security testing to identify similar vulnerabilities in other application components. The vulnerability demonstrates the critical importance of input validation and output encoding practices in web applications, aligning with OWASP Top Ten category A03: Injection, which emphasizes the necessity of proper sanitization of user inputs to prevent various injection attacks including XSS. Security teams must also consider implementing Content Security Policy headers as an additional defense-in-depth measure to mitigate the impact of potential XSS exploitation attempts.