CVE-2021-35211

critical

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.

From the Tenable Blog

CVE-2021-35211: SolarWinds Serv-U Managed File Transfer Zero-Day Vulnerability Exploited in Targeted Attacks

CVE-2021-35211: SolarWinds Serv-U Managed File Transfer Zero-Day Vulnerability Exploited in Targeted Attacks

Published: 2021-07-14

Following a patch for a zero-day vulnerability in SolarWinds’ Serv-U Managed File Transfer, researchers share new details about the attacks, as over 8,000 systems remain publicly accessible and potentially vulnerable.

References

https://www.tenable.com/cyber-exposure/2021-threat-landscape-retrospective

https://research.nccgroup.com/2021/11/08/ta505-exploits-solarwinds-serv-u-vulnerability-cve-2021-35211-for-initial-access/

https://www.microsoft.com/security/blog/2021/07/13/microsoft-discovers-threat-actor-targeting-solarwinds-serv-u-software-with-0-day-exploit/

https://www.tenable.com/blog/cve-2024-28995-solarwinds-serv-u-path-directory-traversal-vulnerability-exploited-in-the-wild

https://www.tenable.com/blog/cve-2021-35211-solarwinds-serv-u-managed-file-transfer-zero-day-exploited-dev-0322

https://www.solarwinds.com/trust-center/security-advisories/cve-2021-35211

https://www.microsoft.com/security/blog/2021/07/13/microsoft-discovers-threat-actor-targeting-solarwinds-serv-u-software-with-0-day-exploit

Details

Source: Mitre, NVD

Published: 2021-07-14

Updated: 2025-03-12

Known Exploited Vulnerability (KEV)

Risk Information

CVSS v2

Base Score: 10

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

Severity: Critical

CVSS v3

Base Score: 10

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Severity: Critical

EPSS

EPSS: 0.94139