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CVE-2021-35247

Improper Input Validation Vulnerability in Serv-U

Published: Jan 7, 2022Updated: Oct 27, 2025 Sources: CVE List NVD BDUCWE-20
NVD MITRE
4.3CVSSMEDIUM
EPSS Score
3.4%
Top 12.8%
CISA KEV
Active Exploitation
Since Jan 21, 2022
Exploits
No Known Exploits
Remediation
Patch Available

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.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:RS:UC:NI:LA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:RUser Interaction
Required
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:LIntegrity
Low
A:NAvailability
None
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Weaknesses

CWE-20NVD-CWE-noinfo

Affected Products

Serv-USolarWinds
On-premWeb App
Enterprise Software / itsm-monitoring
Serv-U File ServerSolarWinds Inc.
On-prem
Enterprise Software / itsm-monitoring
serv-usolarwinds
On-premWeb App
Enterprise Software / itsm-monitoring
solarwindscommercialUSEnterprise Softwareaka solar winds
solarwinds inc.commercialUSEnterprise Softwareaka solarwinds orion platform, serv-u file server, access rights manager

Attack Graph

Products CVE Techniques Tactics

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Exploitability

CISA Known Exploited Vulnerability
Added to KEV:Jan 21, 2022
Remediation due:Feb 4, 2022

Required action: Apply updates per vendor instructions.

Official Patch Available

MITRE ATT&CK

1 technique
Initial Access
View detailed technique mapping

References

https://www.solarwinds.com/trust-center/security-advisories/cve-2021-35247
solarwinds.com
https://documentation.solarwinds.com/en/success_center/servu/content/release_notes/servu_15-3_release_notes.htm
documentation.solarwinds.com
https://www.solarwinds.com/trust-center/security-advisories/cve-2021-35247
solarwinds.com
and 2 more references View all →

Timeline

Published
Jan 7, 2022
Added to CISA KEV
Jan 21, 2022
Last Updated
Oct 27, 2025

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