CVE DatabaseCVE-2025-40551

Updated 2026-06-17한국어 권고문 →

CVE-2025-405519.8/CRITICALCISA KEVCWE-502

SolarWinds Web Help Desk Untrusted Data Deserialization Vulnerability (CVE-2025-40551) Remote Code Execution (RCE) Security Advisory

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Affected Vendors

solarwinds

Affected Components

web help desk

Published Date

2026-01-28

CVSS v3.1

9.8

CRITICAL

EPSS (30d)

84.2%

FIRST.org

CISA KEV

Exploited

NVD Source ↗

Executive & SecOps Summary

SECOPS ASSESSMENT

Affected Scope

SolarWinds Web Help Desk (WHD) versions prior to 2026.1

Impact

Unauthenticated remote attackers can execute arbitrary system commands with high privileges on the host machine by sending specially crafted serialized data

Mitigation

Immediately upgrade SolarWinds Web Help Desk to version 2026.1 or higher, and restrict external network access to the service

Affected Products & Version Scope

All SolarWinds Web Help Desk (WHD) versions prior to 2026.1 (Active exploitation reported)

Remediation & Live Workaround Commands

PATCH & WORKAROUND

1. Official Patch & Version Upgrade Commands

According to the SolarWinds security advisory, administrators must immediately upgrade Web Help Desk to version 2026.1 or later. Below is an example procedure to stop the service and apply the patch on a Linux host.

bash

# 1. Stop the running Web Help Desk service
sudo systemctl stop webhelpdesk

# 2. Download and extract the latest secure package from the SolarWinds Customer Portal
# tar -zxvf webhelpdesk-2026.1.x.x.tar.gz

# 3. Execute the upgrade script and restart the service
sudo ./upgrade_whd.sh
sudo systemctl start webhelpdesk
sudo systemctl status webhelpdesk

2. Temporary Workaround & Hardening Configuration

If patching cannot be applied immediately, restrict access to the WHD service ports (default TCP 8443, 8081) using firewalls or security groups. Limit access exclusively to trusted internal IP ranges or VPN gateways.

bash

# Restrict external access using iptables, allowing only a trusted admin IP (e.g., 192.168.10.50)
sudo iptables -A INPUT -p tcp -s 192.168.10.50 --dport 8443 -j ACCEPT
sudo iptables -A INPUT -p tcp --dport 8443 -j DROP

# Save the iptables configuration (Debian/Ubuntu)
sudo apt-get install iptables-persistent -y
sudo netfilter-persistent save

3. Log Audit & IoC Verification Commands

Inspect the WHD installation log directories for abnormal Java deserialization exceptions (such as java.io.InvalidClassException or ObjectInputStream errors) and suspicious system command executions.

bash

# Search for deserialization-related exceptions in WHD logs
grep -ri 'java.io.ObjectInputStream' /usr/local/webhelpdesk/log/
grep -ri 'InvalidClassException' /usr/local/webhelpdesk/log/

# Verify the running process privileges and check the current installed version
ps -ef | grep webhelpdesk
cat /usr/local/webhelpdesk/conf/version.txt 2>/dev/null || echo 'Version check required'

Interactive SecOps Remediation Checklist

0/4 (0%)

Recommended Security Control & Mitigation Partner

Cloudflare Enterprise & Pro WAF

Due to active exploitation in the wild (CISA KEV), immediately upgrade SolarWinds Web Help Desk to version 2026.1 or higher.

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Technical Root Cause & Exploitation Mechanics

1. Vulnerability Overview & Root Cause

This vulnerability (CVE-2025-40551) is an untrusted data deserialization flaw (CWE-502) residing within SolarWinds Web Help Desk (WHD). The root cause lies in the Java-based WHD application deserializing untrusted input data without sufficient validation or filtering. An attacker can exploit this by reconstructing Java object streams to trigger vulnerable gadget chains present within the application's classpath.

2. Exploitation Mechanics & Attack Scenario

An attacker can exploit this vulnerability remotely without any prior authentication or user interaction (AV:N/AC:L/PR:N/UI:N). By sending a malicious serialized Java object payload to an exposed endpoint processed by ObjectInputStream or similar mechanisms, the attacker triggers the deserialization process. This leads to immediate execution of arbitrary operating system commands in the context of the WHD process. This vulnerability is actively exploited in the wild and is listed in the CISA KEV catalog.

3. Infrastructure & Business Impact

With a CVSS 3.1 score of 9.8 (Critical), the impact of this vulnerability is severe. Successful exploitation grants the attacker complete control over the host operating system, allowing them to establish a persistent foothold and pivot further into the internal corporate network. Given that help desk systems store sensitive employee credentials, customer support tickets, and system configurations, a breach could lead to massive data exfiltration and severe reputational damage.

Official Vendor Advisories & References

NVD Original English Description

SolarWinds Web Help Desk was found to be susceptible to an untrusted data deserialization vulnerability that could lead to remote code execution, which would allow an attacker to run commands on the host machine. This could be exploited without authentication.

https://documentation.solarwinds.com/en/success_center/whd/content/release_notes/whd_2026-1_release_notes.htm

Source: psirt@solarwinds.com · Release Notes

https://www.solarwinds.com/trust-center/security-advisories/CVE-2025-40551

Source: psirt@solarwinds.com · Vendor Advisory

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-40551

Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0 · US Government Resource

Frequently Asked SecOps Questions (CVE-2025-40551)

FAQ

Q1. How critical is CVE-2025-40551 and is it actively exploited in the wild?

CVE-2025-40551 is rated CVSS 9.8 (CRITICAL) with a 30-day EPSS exploitation probability of 84.2%. It is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, requiring immediate emergency remediation.

Q2. Which vendors and products are affected by CVE-2025-40551?

Primary impacted vendors include solarwinds across web help desk. Scope summary: All SolarWinds Web Help Desk (WHD) versions prior to 2026.1 (Active exploitation reported)

Q3. What temporary mitigations or workarounds exist for CVE-2025-40551 before patching?

[Mitigation] Immediately upgrade SolarWinds Web Help Desk to version 2026.1 or higher, and restrict external network access to the service Follow the CLI remediation commands and interactive SecOps checklist on this page to restrict exposure prior to your maintenance window.

SECOPS WORKBENCH INTEGRATION