Actively Exploited — CISA KEV

CVE-2025-40536: SolarWinds Web Help Desk High-Severity Vulnerability

Severity: High | CVSS 3.1: 8.1 | Published: 2026-01-28 | KEV Added: 2026-02-12

What is CVE-2025-40536?

SolarWinds Web Help Desk was found to be susceptible to a security control bypass vulnerability that if exploited, could allow an unauthenticated attacker to gain access to certain restricted functionality.

Technical Analysis

Weakness Classification

This vulnerability is classified as CWE-693.

Attack Vector Breakdown

  • Attack Vector: Network
  • Attack Complexity: High
  • Privileges Required: None
  • User Interaction: None
  • Scope: Unchanged
  • Confidentiality: High
  • Integrity: High
  • Availability: High

Impact Analysis

This vulnerability is exploitable over the network, meaning any system reachable via the internet or internal network is potentially at risk without physical access. Successful exploitation can result in full confidentiality breach (complete data disclosure), complete integrity compromise (data modification or code execution), total availability loss (denial of service).

Exploitation Probability (EPSS): 67.5% chance of exploitation in the next 30 days (99th percentile). This places the vulnerability in the highest risk tier — immediate action is critical.

Is CVE-2025-40536 being exploited?

Yes. CVE-2025-40536 is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, restricted to CVEs with confirmed active exploitation in the wild. CISA added this vulnerability on 2026-02-12. Inclusion in KEV triggers the patching mandate under BOD 22-01 for U.S. federal civilian agencies, with a remediation deadline of 2026-02-15.

How to fix CVE-2025-40536

Apply the security update issued by SolarWinds for Web Help Desk. If an immediate patch is not possible, consult the vendor advisory for mitigation guidance, restrict network exposure of the affected service, and monitor logs for indicators of exploitation. CISA's Known Exploited Vulnerabilities catalog requires U.S. federal agencies to remediate this vulnerability by the due date shown below under Binding Operational Directive 22-01. Private organizations should treat KEV entries as priority-one patches because active exploitation has been confirmed in the wild.

Related Vulnerabilities

Other actively exploited vulnerabilities affecting Web Help Desk or sharing the same weakness (CWE-693):

  • CVE-2025-26399 (Critical 9.8) [same product] — SolarWinds Web Help Desk was found to be susceptible to an unauthenticated…
  • CVE-2025-40551 (Critical 9.8) [same product] — SolarWinds Web Help Desk was found to be susceptible to an untrusted data…
  • CVE-2026-28318 (High 7.5) [same vendor] — SolarWinds Serv-U is susceptible to specially crafted POST requests that crash…
  • CVE-2026-32202 (Medium 4.3) [same CWE] — Protection mechanism failure in Windows Shell allows an unauthorized attacker…
  • CVE-2026-21513 (High 8.8) [same CWE] — Protection mechanism failure in MSHTML Framework allows an unauthorized…

Frequently asked questions

Is CVE-2025-40536 critical?

CVE-2025-40536 has a CVSS 3.1 base score of 8.1 — High severity. It should be treated as a priority patch, especially given the active exploitation confirmed by CISA.

Is CVE-2025-40536 being actively exploited?

Yes — CISA added CVE-2025-40536 to the Known Exploited Vulnerabilities catalog on 2026-02-12. Inclusion in KEV means CISA has confirmed in-the-wild exploitation.

How do I patch CVE-2025-40536?

Apply the security update from SolarWinds for Web Help Desk. Federal agencies must remediate by 2026-02-15 under BOD 22-01.

What type of vulnerability is CVE-2025-40536?

CVE-2025-40536 is classified under CWE-693.

What is the CVSS score for CVE-2025-40536?

CVE-2025-40536 has a CVSS 3.1 base score of 8.1, classifying it as High severity. The attack vector is Network, attack complexity is High, and no privileges are required.