CVE-2021-35211KEV · OVERDUE

Serv-U Remote Memory Escape Vulnerability

Critical · published July 14, 2021

Patch now

Confirmed exploited, and the score agrees

CVSS calls it critical at 9.0. It is confirmed in active exploitation. It sits in the 99.8th percentile for exploit probability.

1801
days past CISA
deadline
CVSS v3.1
9.0
EPSS
91%
Percentile
99.8
In the wild
Confirmed
What it is

🚨 A remote code execution vulnerability in SolarWinds Serv-U is a game-changer, allowing attackers to take control of the host machine! 🔥 Think of the Serv-U product as a hotel concierge who can grant access to any room in the building. If an unauthorized guest figures out how to trick that concierge, they could roam freely, accessing sensitive areas without any checks or balances. If exploited, a malicious actor could gain privileged access to the machine hosting Serv-U, leading to potentially devastating consequences like data breaches, service disruptions, and unauthorized access to critical systems.

Put simply

Think of the Serv-U product as a hotel concierge who can grant access to any room in the building. If an unauthorized guest figures out how to trick that concierge, they could roam freely, accessing sensitive areas without any checks or balances. CVE-2021-35211 is a remote code execution vulnerability caused by a Remote Memory Escape flaw in SolarWinds Serv-U, affecting versions prior to 15.2.3 HF2. This flaw allows attackers to execute arbitrary code on the server where Serv-U is running, compromising its security.

What to do

If exploited, a malicious actor could gain privileged access to the machine hosting Serv-U, leading to potentially devastating consequences like data breaches, service disruptions, and unauthorized access to critical systems. Immediately upgrade SolarWinds Serv-U to version 15.2.3 HF2 or later to patch this vulnerability. Additionally, conduct a security audit to ensure no unauthorized access has taken place. Implement strict access controls to further reduce risks. You've got this! With quick action, you can safeguard your systems against this critical vulnerability. 🛡️

The record
Technical detail
CVSS v3.1
9.0 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.91160 · 99.8th percentile
Published
2021-07-14T20:55Z
KEV added
2021-11-03 · due 2021-11-17
EPSS history
Timeline
  • 03 NOV 00:00Z
    Added to CISA KEV — remediate by Nov 17
    kev
  • 14 JUL 20:55Z
    Serv-U Remote Memory Escape Vulnerability
    cvelistv5