CVE-2026-81477: Dell OpenManage Server Administrator RCE

CVE-2026-81477 Overview

CVE-2026-81477 is a heap-based buffer overflow vulnerability [CWE-122] in Dell OpenManage Server Administrator (OMSA) versions prior to 11.1.0.3. A remote attacker with high privileges can exploit the flaw to execute arbitrary code on the affected system. The vulnerability affects the network-accessible management interface of OMSA, which administrators use to monitor and manage Dell PowerEdge server hardware.

Dell published the fix in advisory DSA-2026-403 and remediated the issue in OMSA version 11.1.0.3.

Critical Impact
Successful exploitation results in code execution on the host running Dell OpenManage Server Administrator, compromising confidentiality, integrity, and availability of the managed server.

Affected Products

Dell OpenManage Server Administrator (OMSA) versions prior to 11.1.0.3

Discovery Timeline

2026-09-17 - CVE-2026-81477 published to NVD
2026-09-17 - Last updated in NVD database

Technical Details for CVE-2026-81477

Vulnerability Analysis

Dell OpenManage Server Administrator contains a heap-based buffer overflow in a network-reachable component. When the vulnerable code processes attacker-supplied input, it writes beyond the boundary of a heap-allocated buffer. This corrupts adjacent heap metadata and application data structures, which an attacker can shape to redirect execution flow.

Code execution occurs in the security context of the OMSA service. On typical deployments, OMSA runs with elevated privileges to interface with hardware management components, so successful exploitation yields high-impact control of the managed server.

Root Cause

The root cause is improper validation of input size prior to a heap buffer write, classified as [CWE-122] Heap-based Buffer Overflow. The vulnerable routine allocates a fixed or attacker-influenced buffer and copies data without enforcing correct length checks against the destination boundary.

Attack Vector

The attack vector is network-based. The attacker must already hold high privileges on the target environment, which limits pre-authenticated exploitation. User interaction is not required. The attacker sends crafted requests to the OMSA management interface to trigger the overflow and achieve code execution. See the Dell Security Update for OMSA for vendor-supplied technical details.

No verified proof-of-concept code is publicly available at the time of publication. The vulnerability mechanism is documented in prose only, consistent with the absence of released exploit artifacts.

Detection Methods for CVE-2026-81477

Indicators of Compromise

Unexpected child processes spawned by the OMSA service account or dsm_om_connsvc on Windows and Linux hosts running OpenManage Server Administrator.
Crash events, service restarts, or memory faults recorded in OMSA logs or the host event log tied to the management daemon.
Anomalous inbound connections to OMSA management ports (default 1311/TCP) from unusual internal sources.

Detection Strategies

Inventory all hosts running Dell OpenManage Server Administrator and compare installed versions against 11.1.0.3 to identify vulnerable systems.
Monitor process lineage from OMSA services for unexpected shells, scripting interpreters, or persistence-related binaries.
Alert on segmentation faults, access violations, and abnormal termination of OMSA processes that may indicate exploitation attempts.

Monitoring Recommendations

Log and review authenticated administrative sessions against the OMSA web interface, focusing on privileged accounts.
Capture network telemetry for the OMSA management port and baseline expected management traffic sources.
Forward endpoint and network telemetry to a centralized analytics platform for correlation with authentication and change-management events.

How to Mitigate CVE-2026-81477

Immediate Actions Required

Upgrade Dell OpenManage Server Administrator to version 11.1.0.3 or later as directed in Dell advisory DSA-2026-403.
Restrict network access to the OMSA management interface using host firewalls or network ACLs so only trusted administration subnets can reach it.
Rotate credentials for administrative accounts with access to OMSA if compromise is suspected.

Patch Information

Dell released the fix in OMSA 11.1.0.3. Refer to the Dell Security Update for OMSA advisory for download links and upgrade guidance.

Workarounds

Where immediate patching is not possible, isolate OMSA hosts behind a management VLAN accessible only from a bastion host.
Disable remote access to the OMSA web interface and require local console or jump-host access for administrative tasks until the patch is applied.
Enforce least privilege on accounts that can authenticate to OMSA, minimizing the set of users capable of reaching the vulnerable code path.

bash

# Configuration example: restrict inbound access to OMSA management port (Linux iptables)
iptables -A INPUT -p tcp --dport 1311 -s 10.0.10.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 1311 -j DROP