CVE-2026-79829 in NonStop HTTP WEBSERVER
Summary
by MITRE • 10/15/2026
A security vulnerability in HPE NonStop HTTP WEBSERVER can cause memory corruption which may result in a system halt.
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Analysis
by VulDB Data Team • 10/15/2026
The HPE NonStop HTTP Webserver, a critical component for delivering web-based services on the NonStop platform, contains a flaw that leads to heap or stack memory corruption under specific conditions. This vulnerability typically arises from improper handling of input data within the server's request parsing logic. When an attacker sends a specially crafted HTTP request containing malformed headers, excessively long fields, or unexpected character sequences, the webserver fails to validate the boundaries and types of this data correctly. Instead of rejecting the invalid input gracefully, the application attempts to process it in a way that writes beyond allocated memory buffers. This out-of-bounds write operation overwrites adjacent memory structures, corrupting critical control data such as function return addresses or object pointers within the server's runtime environment.
The immediate operational impact of this memory corruption is severe instability within the webserver process. Because HPE NonStop systems rely heavily on high availability and continuous uptime for mission-critical applications, any disruption to core services like HTTP serving can have significant business consequences. The specific manifestation described in reports indicates that the corruption triggers a fatal error condition leading to an automatic system halt or crash of the affected server instance. This results in a denial of service (DoS) for clients attempting to access resources hosted on this webserver. While there is no direct indication of arbitrary code execution, memory corruption vulnerabilities are often precursors to more severe exploits if the attacker can control the overwritten data precisely enough to redirect program flow. However, even without remote code execution capabilities, the ability to crash the service constitutes a serious availability risk that undermines the reliability guarantees expected from enterprise-grade infrastructure.
From a classification perspective, this vulnerability aligns with CWE-120 Buffer Overflow and CWE-787 Out-of-bounds Write, as the root cause is insufficient validation of input length or type leading to memory boundary violations. In terms of attack vectors, it falls under MITRE ATT&CK technique T1499 Endpoint Denial of Service, specifically via resource exhaustion through application crashes. The vulnerability likely exists in versions of HPE NonStop HTTP Webserver prior to the release of specific security patches that address input sanitization and buffer management routines. Attackers can exploit this remotely if the web server is exposed to untrusted networks without adequate front-end protection or rate limiting mechanisms, although successful exploitation requires precise crafting of malicious payloads tailored to the internal memory layout of the software version in use.
Mitigation strategies should prioritize immediate patching by applying vendor-recommended updates that correct the input validation logic and enforce strict buffer size limits during request processing. In environments where patching is not immediately feasible, network-level controls such as Web Application Firewalls (WAF) can be configured to detect and block anomalous HTTP requests containing oversized headers or suspicious character patterns before they reach the vulnerable application layer. Additionally, administrators should ensure that the web server runs with minimal privileges to limit potential damage if a crash occurs, although this does not prevent the denial of service itself. Regular monitoring for unexpected process restarts or system halts associated with the httpd service can aid in early detection of exploitation attempts. Maintaining strict input validation standards and adhering to secure coding practices are essential long-term measures to prevent similar memory safety issues across all web-facing applications on the platform.