Security news, read and ranked every 30 minutes.
Exploited. On CISA's list since 2021-11-03, and used by ransomware.
CVE-2021-35211 · SolarWinds Serv-U · Published 2021-07-14
10.0 out of 10
CVSS rates it critical: about as damaging as flaws get.
91%
Estimated chance of exploitation in the next 30 days, among the top 1% of all scored flaws (EPSS, 2026-10-29).
Yes
CISA has seen it exploited in real attacks. For US government agencies the fix is deadline passed 1808 days ago (2021-11-17).
Apply updates per vendor instructions.
SolarWinds Serv-U contains an unspecified memory escape vulnerability which can allow for remote code execution.
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 NVD.
Explore this week’s weaknesses and all learning topics
Understand the kind of weakness behind this flaw. These resources teach the weakness, rather than reproduce this specific CVE. Follow the vendor's advice above to fix the affected product.
A program writes outside the memory region it is allowed to use.
CWE-787 · CISA KEV; NVD record: 134c704f-9b21-4f2e-91b3-4a467353bcc0; NVD record: nvd@nist.gov
Video course · Free course. C programming and memory concepts are useful; covers several weakness types.
CWE is a catalogue of weakness types. Labels come from the sources shown and can differ or change. Resource matches reviewed 16 October 2026.
No story in the last 14 days has mentioned it.
Exploited flaws from CISA's KEV catalogue. Chance of exploitation from EPSS by FIRST. Descriptions and scores from the NVD. This product uses the NVD API but is not endorsed or certified by the NVD.