How severe is CVE-2025-26399?

CVE-2025-26399 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2025-26399 being actively exploited?

Yes. CVE-2025-26399 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2026-03-09, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2025-26399?

CVE-2025-26399 primarily affects Solarwinds Web Help Desk. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-26399?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2025-26399 have an EU (EUVD) identifier?

Yes. CVE-2025-26399 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-30842. It is also flagged as exploited in the EUVD (since 2026-03-09).

When was CVE-2025-26399 published?

CVE-2025-26399 was published on 2025-09-23 and last updated on 2026-06-17.

CVE-2025-26399

CVE-2025-26399 is a critical-severity vulnerability in Solarwinds Web Help Desk with a CVSS 3.x base score of 9.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2026-03-09). The underlying weakness is classified as CWE-502.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 88% (100th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2026-03-09)
EU (EUVD) id: EUVD-2025-30842
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2026-03-09)
Weakness: CWE-502
Affected product: Solarwinds Web Help Desk
Published: 2025-09-23
Last modified: 2026-06-17

Description

SolarWinds Web Help Desk was found to be susceptible to an unauthenticated AjaxProxy deserialization remote code execution vulnerability that, if exploited, would allow an attacker to run commands on the host machine. This vulnerability is a patch bypass of CVE-2024-28988, which in turn is a patch bypass of CVE-2024-28986.

Frequently asked questions

What is CVE-2025-26399?: SolarWinds Web Help Desk was found to be susceptible to an unauthenticated AjaxProxy deserialization remote code execution vulnerability that, if exploited, would allow an attacker to run commands on the host machine. This vulnerability is a patch bypass of CVE-2024-28988, which in turn is a patch bypass of CVE-2024-28986.
How severe is CVE-2025-26399?: CVE-2025-26399 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-26399 being actively exploited?: Yes. CVE-2025-26399 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2026-03-09, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2025-26399?: CVE-2025-26399 primarily affects Solarwinds Web Help Desk. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-26399?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2025-26399 have an EU (EUVD) identifier?: Yes. CVE-2025-26399 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-30842. It is also flagged as exploited in the EUVD (since 2026-03-09).
When was CVE-2025-26399 published?: CVE-2025-26399 was published on 2025-09-23 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:solarwinds:web_help_desk:*:*:*:*:*:*:*:*
cpe:2.3:a:solarwinds:web_help_desk:12.8.7:-:*:*:*:*:*:*

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