CVE-2025-40547
Solarwinds Serv-U ≤ 15.5.3
Raw vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:HSummary
CVE-2025-40547 is a critical-severity Improper Encoding or Escaping of Output (CWE-116) vulnerability in Solarwinds Serv-U. Its CVSS base score is 9.1 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Content Injection (T1659); ranked in the top 45% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
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-2025-40547 is a logic error vulnerability in SolarWinds Serv-U that enables a malicious actor with administrative privileges to execute arbitrary code. The issue, published on 2025-11-18, carries a CVSS v3.1 base score of 9.1 (AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H) and is associated with CWE-116 (Improper Encoding or Escaping of Output).
Exploitation requires high-privilege administrative access to the affected Serv-U instance. A successful attack allows the adversary to achieve high impacts on confidentiality, integrity, and availability, with a changed scope due to the privileged code execution. On Windows deployments, the overall risk is rated as medium, as Serv-U services typically run under less-privileged accounts by default, potentially limiting the blast radius even if admin credentials are compromised.
SolarWinds has published a security advisory detailing the issue at https://www.solarwinds.com/trust-center/security-advisories/CVE-2025-40547, along with release notes for Serv-U version 15.5.3 at https://documentation.solarwinds.com/en/success_center/servu/content/release_notes/servu_15-5-3_release_notes.htm, which address mitigation through patching.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-197930
Vulnerability Data
A logic error vulnerability exists in Serv-U which when abused could give a malicious actor with access to admin privileges the ability to execute code. This issue requires administrative privileges to abuse. On Windows deployments, the risk is scored as…
more
a medium because services frequently run under less-privileged service accounts by default.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
—
—
—
V1.1.2V1.2.1V1.2.3
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Validating that output matches expected content directly mitigates failures to properly encode or escape data for its destination context.
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.
Secure SDLC practices directly require proper output encoding to prevent injection and message malformation.
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.
Secure coding standards explicitly require correct output encoding and escaping to preserve message structure.
Security testing can detect missing or incorrect encoding but does not itself implement the control.
Secure development life cycle mandates output encoding/escaping practices that directly prevent improper encoding.
Application security requirements include explicit rules for safe output handling and encoding.
Secure architecture principles reduce the likelihood of missing encoding but do not prescribe the actual technique.