CVE-2021-35211

Known Exploited
Serv-U Remote Memory Escape Vulnerability

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.

Remediation

Solution:

  • SolarWinds has released a hotfix 15.2.3 HF2 It is suggested to upgrade to the latest hotfix as soon as possible

Workaround:

  • SolarWinds advises to disconnect Serv-U Server from internet until patched.

Category

9.0
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 94.14% Top 5%
KEV Since 
Vendor Advisory microsoft.com Vendor Advisory solarwinds.com
Affected: SolarWinds Serv-U Managed File Transfer Server and Serv-U Secured FTP
Published at:
Updated at:

References

Link Tags
https://www.solarwinds.com/trust-center/security-advisories/cve-2021-35211 patch vendor advisory
https://www.microsoft.com/security/blog/2021/07/13/microsoft-discovers-threat-actor-targeting-solarwinds-serv-u-software-with-0-day-exploit patch vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-35211?
CVE-2021-35211 has been scored as a critical severity vulnerability.
How to fix CVE-2021-35211?
To fix CVE-2021-35211: SolarWinds has released a hotfix 15.2.3 HF2 It is suggested to upgrade to the latest hotfix as soon as possible
Is CVE-2021-35211 being actively exploited in the wild?
It is confirmed that CVE-2021-35211 is actively exploited. Be extra cautious if you are using vulnerable components. According to its EPSS score, there is a ~94% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-35211?
CVE-2021-35211 affects SolarWinds Serv-U Managed File Transfer Server and Serv-U Secured FTP.
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