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IMMUNITYSEC

CVE-2021-35211

Serv-U Remote Memory Escape Vulnerability

9.0
CRITICAL
CVSS 3.1
EPSS 91.2% · 100th pctCISA KEV · Exploited in the wild
2021-07-14•Updated 2025-10-21•KEV 2021-11-03
CISA Known Exploited Vulnerabilities

SolarWinds Serv-U Remote Code Execution Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.

Added to KEV
2021-11-03
Remediation due
2021-11-17
Ransomware
Known use

Required action
Apply updates per vendor instructions.

CISA notes
https://nvd.nist.gov/vuln/detail/CVE-2021-35211

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.

Severity

CVSS 3.1 · CNA9 CRITICAL
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
SSVC · CISA-ADP
Exploitationactive
Automatableno
Technical impacttotal

Affected Products

VendorProductAffected versions
SolarWindsServ-U Managed File Transfer Server and Serv-U Secured FTP
SolarWinds Serv-U to <15.2.3 HF1

References

2 Links

Record Details

Published
2021-07-14
Last updated
2025-10-21
Assigner (CNA)
SolarWinds
Credited to
SolarWinds would like to thank the Microsoft Threat Intelligence Center (MSTIC) and Microsoft Offensive Security Research teams for reporting on the issue in a responsible manner.

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CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.