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CVE-2021-35211

Serv-U Remote Memory Escape Vulnerability

Published: Jul 14, 2021Updated: Oct 27, 2025 Sources: CVE List NVD BDUCWE-787
9.0CRITICAL
NVD MITRE
EPSS Score
91.2%
Top 0.2%
CISA KEV
Active Exploitation
Since Nov 3, 2021
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
Nuclei · OpenVAS

Description

Microsoft discovered a remote code execution (RCE) vulnerability in the SolarWinds Serv-U product utilizing a Remote Memory Escape Vulnerability. If exploited, a threat actor may be able to gain privileged access to the machine hosting Serv-U Only. SolarWinds Serv-U Managed File Transfer and Serv-U Secure FTP for Windows before 15.2.3 HF2 are affected by this vulnerability.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:HPR:NUI:NS:CC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:CScope
Changed
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
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Weaknesses

CWE-787

Affected Products

SolarWinds
commercial·USaka solar winds
Serv-U Managed File Transfer Server and Serv-U Secured FTPOn-premWeb App
Enterprise Software / itsm-monitoring
serv-uOn-premWeb App
Enterprise Software / itsm-monitoring
SolarWinds Inc.
commercial·USaka solarwinds orion platform, serv-u file server, access rights manager
Serv-U File ServerOn-premWeb App
Enterprise Software / itsm-monitoring

Exploitability

CISA Known Exploited Vulnerability
Added to KEV:Nov 3, 2021
Remediation due:Nov 17, 2021
Ransomware:Known ransomware use

Required action: Apply updates per vendor instructions.

Official Patch Available
Workaround Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://www.solarwinds.com/trust-center/security-advisories/cve-2021-35211
solarwinds.com
https://www.microsoft.com/security/blog/2021/07/13/microsoft-discovers-threat-actor-targeting-solarwinds-serv-u-software-with-0-day-exploit
microsoft.com
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-35211
cisa.gov
and 4 more references View all →
News mentions
2

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