Cyber Resilience

CVE-2025-40549

Path Traversal in Solarwinds Serv-U ≤ 15.5.3

Path Traversal
Published
18 November 2025
Modified
02 December 2025
Patch / advisory
View advisory
CVSS Score v3.1 9.1
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.010 61th percentile
Risk Priority 61 floored blend · peak EPSS

Summary

CVE-2025-40549 is a critical-severity Path Traversal (CWE-22) vulnerability in Solarwinds Serv-U. Its CVSS base score is 9.1 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 39% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2025-40549 is a Path Restriction Bypass vulnerability (CWE-22) in Serv-U. This issue affects Serv-U, where abuse enables a malicious actor with administrative privileges to execute code on a directory. The vulnerability carries a CVSS v3.1 base score of 9.1 (Critical), with the vector AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H. On Windows systems, it is assessed as medium severity due to differences in path and home directory handling.

Exploitation requires administrative privileges, limiting it to attackers who have already gained admin-level access to the Serv-U instance. A successful attack allows the actor to bypass path restrictions and execute code on a directory, resulting in high impacts to confidentiality, integrity, and availability, compounded by the changed scope (S:C) in the CVSS metrics.

SolarWinds has published a security advisory detailing the issue at https://www.solarwinds.com/trust-center/security-advisories/CVE-2025-40549. Mitigation information, including patches, is covered in the Serv-U 15.5.3 release notes at https://documentation.solarwinds.com/en/success_center/servu/content/release_notes/servu_15-5-3_release_notes.htm.

OWASP Top 10 for Web (2025)

A01:2025 Broken Access Control

EU & UK References

Vulnerability Data

A Path Restriction Bypass vulnerability exists in Serv-U that when abused, could give a malicious actor with access to admin privileges the ability to execute code on a directory. This issue requires administrative privileges to abuse. On Windows systems, this…

more

scored as medium due to differences in how paths and home directories are handled.

CWE(s)
CWE-22

Related Threats

MITRE ATT&CK Enterprise Techniques

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-45711Same product: Solarwinds Serv-U
CVE-2024-28073Same product: Solarwinds Serv-U
CVE-2024-28995Same product: Solarwinds Serv-U
CVE-2024-23472Same product class: network monitoring / SIEM
CVE-2023-35187Same product class: network monitoring / SIEM
CVE-2023-33227Same product class: network monitoring / SIEM
CVE-2024-45709Same product class: network monitoring / SIEM
CVE-2023-40055Same product class: network monitoring / SIEM
CVE-2024-23476Same product class: network monitoring / SIEM
CVE-2023-23842Same product class: network monitoring / SIEM

Affected Assets

solarwinds
serv-u
≤ 15.5.3

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V5.3.2

Mitigating Controls (NIST 800-53 r5) AI

AC-3 Access Enforcement good match

Enforces the intended directory access authorizations that path traversal would otherwise bypass.

SI-10 Information Input Validation good match

Input validation directly neutralizes special path elements before pathname construction occurs.

AC-6 Least Privilege partial match

Least privilege reduces the impact of any unauthorized file access obtained via traversal.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-02 partial match
prevents

Patching/maintenance can remediate known path-traversal flaws in deployed software (partial prevention of exploitability) but does nothing to stop the coding defect from being introduced in the first place.

PR.AA-05 none match
prevents

PR.AA-05 defines and reviews access policies but does not address code-level pathname neutralization, so neither direction prevents CWE-22.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development catches path traversal via static/dynamic analysis.

A.8.25 Secure development life cycle partial match
prevents

Secure SDLC mandates input validation and path sanitization that directly prevent path traversal.

A.8.26 Application security requirements partial match
prevents

Application security requirements include rules for safe file handling and canonicalization.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles require least-privilege file access and directory isolation.

A.8.28 Secure coding partial match
prevents

Secure coding standards explicitly forbid unsafe path construction and mandate safe APIs.

A.8.3 Information access restriction partial match
mitigates

Information access restriction limits which files an application may read or write.

References