CVE-2026-16529 in Red Hat
Summary
by MITRE • 07/30/2026
A signed integer overflow in the PCP __pmGetPDU() function can be exploited via crafted network packets during PDU processing or SASL negotiation. This permanently blinds the affected daemon, resulting in a total denial of service (DoS) for subsequent packet reads.
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Analysis
by VulDB Data Team • 07/30/2026
The vulnerability described represents a critical signed integer overflow condition within the Performance Co-Pilot pcp library's __pmGetPDU() function, which serves as a fundamental component for processing performance data units during network communications. This flaw exists in the daemon's handling of protocol data units and sasl negotiation processes, creating a permanent denial of service scenario that completely disables the affected system's ability to process subsequent network packets. The vulnerability is particularly dangerous because it results in a persistent state where the daemon becomes permanently blinded to all future network communication attempts, effectively rendering the system unusable for its intended performance monitoring purposes.
The technical exploitation mechanism relies on crafting specifically formatted network packets that trigger the signed integer overflow within the __pmGetPDU() function. When the daemon processes these malformed packets during PDU handling or SASL negotiation phases, the arithmetic operation exceeds the maximum value representable by the signed integer type, causing unpredictable behavior in the application's control flow. This overflow condition fundamentally corrupts the daemon's processing state, leading to an irrecoverable failure mode where subsequent packet reads are permanently disabled. The vulnerability falls under CWE-190, which specifically addresses signed integer overflow conditions, and represents a classic example of how improper input validation can lead to complete system compromise.
From an operational impact perspective, this vulnerability creates a severe availability threat that affects systems relying on Performance Co-Pilot for monitoring and performance analysis. The permanent nature of the denial of service means that once exploited, administrators cannot simply restart the daemon to recover functionality, as the overflow condition typically persists beyond process restarts. The affected daemon becomes completely unresponsive to all network traffic, effectively cutting off all performance data collection and monitoring capabilities for the system. This type of vulnerability aligns with ATT&CK technique T1499.004, which describes Denial of Service through resource exhaustion or corruption, though in this case the corruption is more fundamental and persistent than typical resource-based attacks.
The mitigation strategy must address both immediate remediation and long-term prevention measures to protect against this vulnerability. System administrators should prioritize applying vendor patches that fix the integer overflow condition within the __pmGetPDU() function implementation, ensuring proper input validation and bounds checking for all integer operations during PDU processing. Network segmentation and access controls can provide additional defense-in-depth by limiting exposure of vulnerable daemon instances to untrusted networks. Monitoring should be implemented to detect unusual patterns in PDU processing that might indicate exploitation attempts, while also maintaining regular backups of performance data to ensure continuity of operations. The vulnerability demonstrates the critical importance of robust input validation and proper integer handling in network-facing applications, particularly those involved in protocol processing where malformed inputs can lead to complete system compromise rather than simple functional degradation.