# CVE-2021-0027: VMware - Information Disclosure

> Live exploitation tracking for CVE-2021-0027 by the CrowdSec Live Exploit Tracker, built from real-world attack data crowdsourced from CrowdSec's global network.

Page: https://tracker.crowdsec.net/cves/CVE-2021-0027

## Key facts

- **Exploitation phase:** Background Noise. Continuous low-level scanning or exploitation attempts are observed, mostly opportunistic and automated.
- **Public exploit available:** Yes
- **Affected products:** VMware vCenter Server
- **Weaknesses:** CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)
- **Tags:** web_application, enterprise_software

## Description

The vSphere Web Client (FLEX/Flash) contains an unauthorized arbitrary file read vulnerability. A malicious actor with network access to port 443 on vCenter Server may exploit this issue to gain access to sensitive information.

## CrowdSec analysis

[CVE-2021-0027](https://euvd.enisa.europa.eu/vulnerability/CVE-2021-0027) is an Information Disclosure vulnerability affecting VMware vCenter Server. Unauthenticated attackers can exploit this vulnerability to read arbitrary files on the vCenter Server.

CrowdSec has been tracking this vulnerability and its exploits since 9th of December 2021.

CrowdSec network data shows that most actors exploiting CVE-2021-0027 rely on broad, untargeted scans with minimal filtering. The activity is largely automated and opportunistic in nature.
In addition, according to the CrowdSec network, attack volume against CVE-2021-0027 has dipped slightly compared to the previous week. Although still commonly targeted, the decline suggests a cooling-off period. Long-term relevance remains, but attention is waning.

There are no public exploits for this vulnerability. However, it is usually abused by sending crafted requests to the vCenter Server.

## Timeline

- 2021-11-24: CVE Published. CVE-2021-0027 is published to NVD.
- 2021-12-09: Rule Released. CrowdSec releases a rule to detect CVE-2021-0027 exploitation attempts against the CrowdSec Network.
- 2025-09-19: CrowdSec First Seen. CrowdSec observes in-the-wild exploitation of CVE-2021-0027 for the first time.

## References

- https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-21980

## Live exploitation data

The [Live Exploit Tracker page](https://tracker.crowdsec.net/cves/CVE-2021-0027) follows observed exploitation activity for CVE-2021-0027. [Request an API key](https://tracker.crowdsec.net/request-api-key) for full access to its exploitation timeline, attacking IP addresses and blocklists.