CVE-2026-17015 in IBM
Summary
by MITRE • 08/20/2026
IBM i 7.6, 7.5, 7.4, and 7.3 could allow a remote authenticated attacker to cause a denial of service and obtain sensitive information due to an out-of-bounds read.
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Analysis
by VulDB Data Team • 08/25/2026
The vulnerability identified in IBM i operating system versions 7.6, 7.5, 7.4, and 7.3 represents a critical security flaw rooted in improper memory management within the application layer. This specific defect is classified as an out-of-bounds read, which occurs when software reads data from a memory location that lies outside the intended buffer or array boundaries. In the context of IBM i, this vulnerability allows for remote exploitation by authenticated attackers who have established valid credentials on the target system. The presence of authentication requirements indicates that while the attack surface is somewhat restricted to users with existing access privileges, it still poses a significant risk within environments where insider threats or compromised accounts are prevalent.
From a technical perspective, an out-of-bounds read typically arises when input validation mechanisms fail to properly verify the length or index of data before accessing memory structures. When such a check is bypassed or missing, the application may retrieve sensitive information stored in adjacent memory locations that were not intended for public access. This can lead to the disclosure of internal state variables, cryptographic keys, session tokens, or other confidential system data. Furthermore, depending on how the operating system handles these invalid reads and subsequent error conditions, it may trigger unexpected behavior such as application crashes or hangs. These events directly contribute to a denial of service condition, disrupting availability for legitimate users who rely on the IBM i environment for critical business operations.
The operational impact of this vulnerability is twofold, encompassing both confidentiality breaches and availability disruptions. The ability to obtain sensitive information through an out-of-bounds read can expose proprietary data or internal network topology details that could facilitate further attacks against the organization. Simultaneously, the denial of service capability means that attackers can degrade system performance or render services completely inaccessible by triggering repeated crashes or resource exhaustion scenarios associated with handling malformed inputs. This dual impact undermines the core security triad of confidentiality, integrity, and availability, particularly affecting organizations that depend on IBM i for high-uptime enterprise applications.
In terms of industry standard classifications, this vulnerability aligns closely with Common Weakness Enumeration (CWE) ID 125, which defines out-of-bounds read errors as a distinct category of memory safety issues. The exploitation vector corresponds to ATT&CK technique T1078, specifically valid accounts used for lateral movement or privilege escalation scenarios where the attacker leverages existing credentials to extract data and disrupt services. Understanding these mappings helps security teams contextualize the risk within broader threat landscapes and prioritize remediation efforts based on established frameworks rather than isolated incident reports.
Mitigation strategies should focus primarily on applying vendor-provided patches that address the underlying memory handling logic in IBM i versions 7.3 through 7.6. Organizations must ensure their systems are updated to the latest authorized levels provided by IBM, as these updates typically include rigorous input validation and bounds checking improvements. Additionally, implementing network segmentation can limit exposure by restricting access to vulnerable components only from trusted subnets or specific user groups. Monitoring for anomalous behavior associated with high-frequency requests or unusual memory usage patterns may also aid in early detection of exploitation attempts before significant damage occurs. Regular security audits and penetration testing should be conducted to verify that the patching process has effectively neutralized the out-of-bounds read condition across all affected instances.