# CVE-2021-35247: Improper Input Validation Vulnerability in Serv-U

> CVE-2021-35247: Improper Input Validation Vulnerability in Serv-U. CVSS 4.3 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2021-35247
Last updated: 2025-10-21T23:15:49Z

- Published: 2022-01-07 22:39 UTC · Updated: 2025-10-21 23:15 UTC · Assigner: SolarWinds
- CVSS: 4.3 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
- EPSS: 3.5%, 89th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2022-01-21, federal due date 2022-02-04, ransomware use: Unknown
- CWE: CWE-20

## Description

Serv-U web login screen to LDAP authentication was allowing characters that were not sufficiently sanitized. SolarWinds has updated the input mechanism to perform additional validation and sanitization. Please Note: No downstream affect has been detected as the LDAP servers ignored improper characters. To insure proper input validation is completed in all environments. SolarWinds recommends scheduling an update to the latest version of Serv-U.

## CISA required action

Apply updates per vendor instructions.

## Affected vendors and products

- SolarWinds: Serv-U

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2021-35247)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2021-35247)
- [https://documentation.solarwinds.com/en/success\_center/servu/content/release\_notes/servu\_15-3\_release\_notes.htm](https://documentation.solarwinds.com/en/success_center/servu/content/release_notes/servu_15-3_release_notes.htm)
- [https://www.solarwinds.com/trust-center/security-advisories/cve-2021-35247](https://www.solarwinds.com/trust-center/security-advisories/cve-2021-35247)

---

_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


---
Canonical: https://rewindex.com/cve/CVE-2021-35247 · Markdown: https://rewindex.com/cve/CVE-2021-35247.md · JSON: https://rewindex.com/api/v1/cves/CVE-2021-35247 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:11:12.275Z