Serv-U Remote Memory Escape Vulnerability
CVE-2021-35211

10CRITICAL

Key Information:

Vendor
Solarwinds
Status
Serv-u Managed File Transfer Server And Serv-u Secured Ftp
Vendor
CVE Published:
14 July 2021

Badges

💰 Ransomware👾 Exploit Exists🟡 Public PoC🟣 EPSS 93%🦅 CISA Reported

Summary

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.

CISA Reported

CISA provides regional cyber and physical services to support security and resilience across the United States. CISA monitor the most dangerious vulnerabilities and have identifed as being exploited and is known by the CISA as enabling ransomware campaigns.

The CISA's recommendation is: Apply updates per vendor instructions.

Affected Version(s)

Serv-U Managed File Transfer Server and Serv-U Secured FTP Windows SolarWinds Serv-U < 15.2.3 HF1

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2021-35211 - Proof of Concept

CVE-2021-35211
Created by BishopFox

Serv-U-CVE-2021-35211
Created by NattiSamson

References

https://www.solarwinds.com/trust-center/security-advisori...
x_refsource_MISC
https://www.microsoft.com/security/blog/2021/07/13/micros...
x_refsource_MISC

EPSS Score

93% chance of being exploited in the next 30 days.

CVSS V3.1

Score:
10
Severity:
CRITICAL
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Changed

Timeline

  • 🟡

    Public PoC available

  • 💰

    Used in Ransomware

  • 👾

    Exploit known to exist

  • 🦅

    CISA Reported

  • Vulnerability published

  • Vulnerability Reserved

Credit

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.
.