Actively exploited in the wild
SolarWinds Serv-U Remote Code Execution Vulnerability
SolarWinds - Serv-U · Listed in the CISA KEV since 2021-11-03. This indicates confirmed attacks in production environments.
Required action: Apply updates per vendor instructions.
CVE-2021-35211
CriticalCVSS 9.0KEVSummary
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.
Risk Assessment
An attacker can gain privileged access to the server, potentially leading to data theft, system takeover, and further attacks within the network.
Recommendation
Immediately update SolarWinds Serv-U to version 15.2.3 HF2 or later that includes a fix.
Other vulnerabilities in SolarWinds Serv-U
See all- CVE-2026-28321Critical
SolarWinds Serv-U suffers from a broken access control vulnerability that allows arbitrary file read/write, privilege escalation, and code execution as root. Domain administrator access is required; impact is lower on Windows.
- CVE-2026-28317Critical
SolarWinds Serv-U is affected by an insecure direct object reference (IDOR) vulnerability that can lead to privilege escalation. Requires domain administrator access. Impact is lower in Windows deployments.
- CVE-2026-28316Critical
SolarWinds Serv-U is affected by an insecure direct object reference (IDOR) vulnerability that can lead to privilege escalation to a system administrator with the ability to execute commands as the root user. This issue requires a domain account with administrator access. The impact is lower in Windows deployments.
- CVE-2026-28314Critical
Vulnerability in SolarWinds Serv-U involving insecure direct object reference (IDOR) allows account takeover. Authentication is required, impact is lower on Windows deployments.
- CVE-2026-28313Critical
SolarWinds Serv-U is affected by an insecure direct object reference (IDOR) vulnerability that can lead to SMTP hijacking leading to arbitrary account takeover. Impact is lower in Windows deployments.
- CVE-2026-28312Critical
Privilege escalation vulnerability in SolarWinds Serv-U. An attacker can elevate group privileges to system administrator and execute code as root. Impact is lower on Windows.
- CVE-2026-28310Critical
SolarWinds Serv-U is affected by a privilege escalation vulnerability that allows a domain administrator to escalate their user type to that of a system administrator. Impact is lower in Windows deployments.
- CVE-2026-28309Critical
SolarWinds Serv-U is affected by a broken access control vulnerability that allows a domain administrator to create system administrator accounts. Impact is lower in Windows deployments.
- CVE-2026-28308Critical
SolarWinds Serv-U is affected by an IDOR vulnerability that can lead to remote code execution. Domain administrator access is required. Impact is lower on Windows deployments.
- CVE-2026-28307Critical
SolarWinds Serv-U is affected by a privilege escalation vulnerability that allows a domain user group to be elevated into an administrator group. Impact is lower in Windows deployments.
Original NVD description (English source)
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.