Summary
CVE-2026-76745 describes memory corruption vulnerabilities in AOS-S that are reachable by an unauthenticated attacker operating from an adjacent network position. Successful exploitation could allow the attacker to execute arbitrary code. The vulnerability carries a CVSS v3.1 base score of 9.6 (Critical) and is classified under CWE-119, which covers improper restriction of operations within the bounds of a memory buffer. The advisory was published by HPE, and the CVE was assigned by HPE.
The CVSS vector CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H reveals several important characteristics: the attack vector is adjacent (the attacker must be on the same network segment), no privileges or user interaction are required, the scope changes (meaning the exploit can affect components beyond the vulnerable component's security scope), and the impact on confidentiality, integrity, and availability is high in each dimension. This combination makes it one of the most severe vulnerability classes for network infrastructure devices.
Technical Analysis
The core of CVE-2026-76745 is a memory corruption condition in AOS-S. CWE-119, the assigned weakness category, encompasses a broad family of buffer handling flaws including stack-based buffer overflows, heap-based buffer overflows, out-of-bounds reads and writes, and other cases where software performs operations on a memory buffer but does not correctly prevent those operations from accessing memory outside the buffer's intended boundaries.
The description states that the vulnerabilities are reachable by an unauthenticated adjacent attacker. This is a critical distinction from a remotely network-exploitable vulnerability (AV:N). The adjacent attack vector (AV:A) means the attacker must be positioned on the same physical or logical network segment as the target device. In practical terms, this typically means the attacker is on the same subnet, the same Wi-Fi network, the same VLAN, or otherwise within broadcast range. An attacker on the public internet cannot directly reach the vulnerable service without first gaining a foothold on the adjacent network.
The unauthenticated aspect (PR:N) means the attacker does not need any credentials on the target system. No login, no API key, no session token, and no prior authentication of any kind is required to trigger the vulnerability. This significantly lowers the barrier to exploitation compared to authenticated vulnerabilities.
The no user interaction aspect (UI:N) means the exploit does not require any action from a legitimate user of the system. The attacker can trigger the vulnerability autonomously by sending crafted data to the vulnerable service.
The scope change aspect (S:C) is particularly noteworthy. In CVSS v3.1, scope change indicates that the vulnerability can affect resources or components that are beyond the security authority of the vulnerable component itself. For a network switch or infrastructure device, this could mean that exploiting the vulnerability allows the attacker to escape from the vulnerable service's security context into a broader system context, potentially gaining control over the entire device rather than just the vulnerable process.
The combination of memory corruption (CWE-119) with arbitrary code execution capability and scope change suggests that the vulnerability likely involves corruption of control-flow data such as return addresses, function pointers, or vtable entries, or corruption of security-critical data structures that allow the attacker to redirect execution to attacker-controlled code. The specific memory region affected (stack, heap, or other), the exact trigger mechanism, and the specific protocol or service that exposes the vulnerability are not fully disclosed in the available description.
The fact that the description uses the plural vulnerabilities rather than vulnerability suggests that multiple distinct memory corruption issues may have been addressed together under this single CVE identifier, or that the same root cause manifests in multiple locations within the AOS-S codebase.
Affected Software and Versions
The vulnerability affects AOS-S. The specific vendor and product names are not explicitly stated in the provided NVD description fields, but the advisory reference points to HPE (Hewlett Packard Enterprise) support documentation, and the CVE was assigned by HPE. AOS-S is associated with HPE Networking products.
The exact affected version ranges are not specified in the provided description. The HPE support advisory referenced (hpesbnw05156en_us) would contain the definitive list of affected and fixed versions. Readers should consult that advisory directly for version-specific information. Without the version details from the provided data, we cannot enumerate specific affected releases here.
Similarly, the specific fixed or patched versions are not stated in the provided description. The HPE advisory document is the authoritative source for remediation version information.
Impact
The impact of CVE-2026-76745 is severe across all three security dimensions:
- Confidentiality (High): Successful exploitation could allow the attacker to access sensitive information stored on or transiting through the affected device. For a network switch, this could include configuration data, credentials, routing tables, and potentially traffic passing through the device.
- Integrity (High): The attacker could modify data on the affected system. This could include altering device configurations, changing routing behavior, modifying traffic in transit, or replacing legitimate services with malicious ones.
- Availability (High): The attacker could disrupt or deny service. This could involve crashing the device, causing it to reboot, or intentionally degrading network performance.
The scope change (S:C) amplifies these impacts. Rather than being confined to the vulnerable service or process, the attacker's influence can extend to the broader system. In the context of a network infrastructure device, this likely means full device compromise rather than compromise of a single service.
The description explicitly states that successful exploitation could allow an attacker to execute arbitrary code. Arbitrary code execution on a network switch or similar infrastructure device effectively grants the attacker full control over the device, enabling persistent access, traffic interception, lateral movement, and use of the device as a staging point for further attacks against the network.
Exploitation Scenario
The following scenario is illustrative and derived from the factual elements in the CVE description. It is not a claim about the specific exploit path, which is not fully disclosed.
An attacker who has gained a position on the same network segment as a device running a vulnerable version of AOS-S could craft and send specially constructed data to a service exposed by the device. Because no authentication is required (PR:N) and no user interaction is needed (UI:N), the attacker can trigger the memory corruption condition directly by sending the crafted data to the appropriate network service on the device.
The crafted data would be designed to trigger improper memory operations within the vulnerable service, corrupting memory in a way that allows the attacker to redirect the execution flow. Given the scope change characteristic, the attacker's code would execute in a security context beyond that of the originally vulnerable service, potentially at the system or kernel level of the device.
Once arbitrary code execution is achieved, the attacker could install persistent backdoors, modify device configurations to redirect or intercept traffic, disable logging and monitoring, or use the compromised device as a pivot point for attacking other systems on the network.
The adjacent network requirement (AV:A) means the attacker must first establish a presence on the target network. This could be achieved through various means such as compromising another device on the same network, gaining physical access to the network, or exploiting a separate vulnerability that provides network access. Once positioned adjacently, exploitation of CVE-2026-76745 requires no further prerequisites.
Detection and Mitigation
Detection of exploitation attempts for this vulnerability is challenging because the specific protocol, service, and trigger mechanism are not fully disclosed in the available description. However, general detection strategies for memory corruption exploitation on network devices include:
- Monitoring for unexpected crashes or reboots of AOS-S devices, which may indicate failed exploitation attempts.
- Watching for anomalous network traffic patterns on segments where AOS-S devices are deployed, particularly unexpected connections to or from the device.
- Monitoring device logs for signs of configuration changes, unexpected process execution, or other indicators of post-exploitation activity.
- Deploying network intrusion detection systems that can flag unusual protocol traffic directed at infrastructure devices.
Mitigation and remediation steps include:
- Consulting the HPE advisory document (
hpesbnw05156en_us) for the specific patched versions and upgrading to a fixed release as soon as possible. - Restricting network access to management and control plane services on AOS-S devices using ACLs, firewall rules, or network segmentation to limit the attack surface from adjacent networks.
- Implementing network segmentation to limit the number of adjacent positions from which an attacker could reach the vulnerable service.
- Monitoring for and responding to any indicators of compromise on devices that cannot be immediately patched.
- Applying the principle of least privilege to network access, ensuring that only necessary protocols and services are exposed on each network segment.
Until a patch can be applied, network-level controls that limit adjacency to the vulnerable service provide the most effective interim mitigation, given that the attack vector requires an adjacent network position.
Bug Bounty Angle
For bug bounty hunters and offensive security researchers, CVE-2026-76745 highlights several important considerations:
Network infrastructure as a target class: Network switches and infrastructure devices are increasingly recognized as high-value targets in bug bounty programs. These devices often run custom firmware with proprietary protocols and services that may not have received the same level of security scrutiny as mainstream software. Memory corruption vulnerabilities in such devices can have outsized impact due to the device's position in the network.
Adjacent network exploitation: The AV:A attack vector means that exploitation requires adjacency. In a bug bounty context, this affects how a researcher would demonstrate impact. Programs that provide lab environments or VPN access to the target network are more suitable for researching this class of vulnerability. Researchers should understand that the adjacent requirement does not diminish severity as much as it constrains the testing methodology.
Unauthenticated attack surface: The PR:N requirement means the vulnerable service is reachable without credentials. Researchers should focus on identifying services exposed by AOS-S devices that accept unauthenticated input, particularly those handling network protocols, management interfaces, or data parsing functions. Fuzzing these services with crafted inputs is a standard approach for discovering memory corruption conditions.
Scope change as an impact amplifier: The S:C metric indicates that exploitation escapes the vulnerable component's security context. Researchers who can demonstrate scope change in their findings should emphasize this in their reports, as it significantly increases the assessed severity and potential bounty payout.
Firmware analysis: Researchers with access to AOS-S firmware images can perform static and dynamic analysis to identify the specific vulnerable code paths. Techniques include binary analysis with tools like Ghidra or IDA Pro, emulation with frameworks like QEMU or FirmAE, and fuzzing of identified services using tools like AFL or network protocol fuzzers.
Responsible disclosure: This vulnerability was discovered by internal security research at HPE Networking, demonstrating that vendors are actively researching their own products. External researchers who discover similar issues should follow coordinated disclosure practices and report findings through the vendor's security advisory process or any applicable bug bounty program.
Frequently Asked Questions
What is CVE-2026-76745?
CVE-2026-76745 is a Critical (CVSS 9.6) memory corruption vulnerability in AOS-S, reachable by an unauthenticated adjacent attacker. Successful exploitation could allow arbitrary code execution with high impact on confidentiality, integrity, and availability.
Does CVE-2026-76745 require authentication to exploit?
No. The CVSS vector specifies PR:N (No Privileges Required), meaning the attacker does not need any credentials on the target system to trigger the vulnerability.
Can CVE-2026-76745 be exploited over the internet?
Not directly. The attack vector is AV:A (Adjacent), meaning the attacker must be on the same network segment as the target. Direct exploitation from the public internet is not possible without first gaining adjacency.
Where can I find patch information for CVE-2026-76745?
The HPE support advisory document hpesbnw05156en_us, referenced in the CVE entry, contains affected and fixed version information. Consult that document for specific remediation guidance.
Who discovered CVE-2026-76745?
The vulnerability was discovered by internal security research at HPE Networking. The CVE was assigned by HPE.
Discovery and Credits
CVE-2026-76745 was discovered by internal security research at HPE Networking. The CVE was assigned by HPE.
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