Description

IBM WebSphere Application Server 9.0, and 8.5 could allow a remote attacker to inject forged log entries into the server's administrative log.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "5.3",
  "pubDate": "2026-09-14T20:16:39.887Z",
  "pubdate": "2026-09-14T20:16:39.887Z",
  "executiveSummary": "This vulnerability involves a log injection flaw within IBM WebSphere Application Server versions 9.0 and 8.5. The flaw permits a remote, unauthenticated attacker to inject arbitrary, forged log entries into the server's administrative logs. This vulnerability type, classified as Log Injection, undermines the integrity and reliability of system audit trails. By manipulating log files, an attacker can mask malicious activities, mislead forensic investigators, or trigger downstream processing errors in log analysis tools. The primary risk implication is the degradation of system monitoring capabilities and the potential for log poisoning to disrupt security operations center (SOC) monitoring and compliance reporting. Exploitation does not require elevated privileges, and the vulnerability resides in the administrative logging mechanism, which is directly reachable over the network.",
  "technicalDetails": "The vulnerability resides in the administrative logging component of IBM WebSphere Application Server 9.0 and 8.5. It arises from insufficient input validation and sanitization when the server processes incoming requests that are subsequently recorded in the administrative log files. When an attacker sends a specifically crafted request containing malicious character sequences—such as carriage return (CR) and line feed (LF) characters—the application fails to encode these inputs correctly before appending them to the log storage medium.\nThe exploitation flow begins with the attacker identifying an exposed administrative interface or an application endpoint that triggers internal logging procedures. The attacker submits a malformed request, often embedding newline characters that effectively terminate the existing log entry prematurely and force the application to begin a new line. By crafting the payload, the attacker can manufacture an entirely falsified log entry, potentially mimicking legitimate system messages or security alerts.\nBecause the server does not enforce strict input normalization, the crafted payload is injected into the server logs as if it were a valid, system-generated administrative action. This lack of sanitization allows for the injection of arbitrary text into sensitive log files, which may be consumed by automated security monitoring tools or SIEM systems. The post-exploitation impact includes the successful obfuscation of the attacker’s true activities, the potential injection of false positive indicators of compromise (IoCs) to mislead incident response teams, and the exploitation of downstream log management systems that might be vulnerable to secondary attacks, such as cross-site scripting (XSS) if the logs are viewed via a web-based log visualization console.\nThe vulnerability is accessible to remote attackers who have network connectivity to the targeted WebSphere administrative service ports. Successful exploitation occurs by manipulating the HTTP or internal protocol headers that the logging engine processes. There is no requirement for authentication, making this an external-facing vector that allows an attacker to pollute the audit chain without needing prior access to the underlying OS or valid administrative credentials."
}