CVE Intelligence
CISA KEV Critical

CVE-2025-40536 — SolarWinds Web Help Desk Security Control Bypass Vulnerability

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.

Published Jan 28, 2026 · Updated Oct 13, 2026 · Sources: CISA Known Exploited Vulnerabilities, NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: SolarWinds

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

How the score was calculated
  • Confirmed exploitation (CISA KEV)+35
  • Public exploit/PoC (nuclei, metasploit, github)+20
  • EPSS 73.6% (30-day exploitation probability)+15
  • Technical severity (critical)+10

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Confirmed
CISA KEV, listed Feb 12, 2026
EPSS FIRST
73.56%
ahead of 99% of scored CVEs · Oct 14, 2026
Affects
Solarwinds
Web Help Desk
CVSS base
9.8
Critical · 4 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
Active
none · proof-of-concept · active
Automatable
No
can an attacker script the kill-chain steps
Technical impact
Total
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

CISA required action CISA

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

US federal deadline: Feb 15, 2026 — passed 242 day(s) ago

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Solarwinds Web Help Desk).
  2. Treat as emergency remediation: the CVE is in CISA KEV (confirmed exploitation).
  3. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  4. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  5. EPSS ahead of 99% of scored CVEs: prioritize it in the patch queue.
  6. Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Solarwinds Web Help Desk < 2026.1 Vulnerable NIST National Vulnerability Database
Solarwinds Web Help Desk version 12.8.8 HF1 and below Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
9.8 CVSS 3.1 Critical 3.9 5.9 nvd@nist.gov via NIST National Vulnerability Database
8.1 CVSS 3.1 High 2.2 5.9 psirt@solarwinds.com via NIST National Vulnerability Database
8.1 CVSS 3.1 High — — GitHub, Inc. via GitHub Security Advisories
8.1 CVSS 3.1 High — — SolarWinds via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H (score shown at the top: nvd@nist.gov)
Scoring entities (NIST, CNA, ADP) score independently; each score is shown with its origin. For prioritization we use 9.8 (NVD (NIST)) as a conservative provisional reference — not a definitive official score.

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-693

Other CVEs with this weakness →

CISA KEV details CISA

CISA lists a CVE once it has evidence of exploitation against real targets.

Listed
Feb 12, 2026
Federal deadline
Feb 15, 2026
passed 242 day(s) ago
Ransomware use
Unknown

CISA records ransomware use only for campaigns it has confirmed, so “Unknown” means unrecorded, not ruled out. The deadline binds US federal agencies; for everyone else it is a reference date.

Public exploits, PoCs and detection templates

Public code that demonstrates or tests the flaw raises the odds of mass exploitation — and Nuclei templates help find vulnerable assets in your environment.

Metasploit modules

Warning: public PoCs are sometimes disguised malware. Use them only for authorized testing in an isolated environment. This portal does not host exploit code — it only points to the sources.

EPSS over time FIRST

Oct 12, 2026 → Oct 14, 2026 · 3 reading(s) · max 73.56%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
  • Hunt retroactively in logs from before Feb 12, 2026 (KEV listing): exploitation may have started earlier.
web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · solarwinds/web help desk
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • Affected products added · solarwinds/web help desk
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVSS changed · 9.8
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Analyzed
    Oct 13, 2026 · NIST National Vulnerability Database
  • Added to CISA KEV (detected)
    Oct 13, 2026 · CISA Known Exploited Vulnerabilities
  • Record created in this database
    Oct 13, 2026 · CISA Known Exploited Vulnerabilities
  • Added to CISA KEV catalog
    Feb 11, 2026 · CISA
  • CVE published
    Jan 28, 2026 · SolarWinds

Source activity

Repeated readings are counted rather than listed.

  • 2× References added · Oct 13, 2026 – Oct 13, 2026
  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

6 on the record

Elsewhere on this site

Solarwinds
every CVE for this vendor
2026-02
what else CISA listed that month
CWE-693
other pages naming this weakness

Related CVEs (same products)

  • High CVE-2026-28299 SolarWinds Web Help Desk Denial-of-Service Vulnerability Jun 2, 2026
  • Critical CVE-2025-40551 SolarWinds Web Help Desk Deserialization of Untrusted Data Vulnerability KEV Jan 28, 2026
  • High CVE-2025-40537 SolarWinds Web Help Desk Hardcoded Credentials Vulnerability Jan 28, 2026
  • Critical CVE-2025-40552 SolarWinds Web Help Desk Authentication Bypass (CVE-2025-40552) Jan 28, 2026
  • Critical CVE-2025-40553 SolarWinds Web Help Desk: untrusted data deserialization leading to RCE Jan 28, 2026
  • Critical CVE-2025-40554 SolarWinds Web Help Desk Authentication Bypass (CVE-2025-40554) Jan 28, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No fixed version, patch or mitigation documented.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2025-40536 is "SolarWinds Web Help Desk Security Control Bypass Vulnerability", rated Critical. It affects Web Help Desk (Solarwinds); versions are in the scope table. It is in CISA KEV: there is evidence of real-world exploitation. CVSS 9.8 describes technical severity. EPSS 73.56% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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