# CVE-2021-22941: Citrix ShareFile - RCE

> Live exploitation tracking for CVE-2021-22941 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-2021-22941

## Key facts

- **Exploitation phase:** Limited Exploitation. The vulnerability is known but shows very limited attacker interest or exploitation activity.
- **CVSS score:** 9.8
- **Public exploit available:** Yes
- **Affected products:** Citrix ShareFile storage zones controller
- **Weaknesses:** CWE-284 (Improper Access Control)
- **Tags:** enterprise_software, file_sharing

## Description

Improper Access Control in Citrix ShareFile storage zones controller before 5.11.20 may allow an unauthenticated attacker to remotely compromise the storage zones controller.

## CrowdSec analysis

[CVE-2021-22941](https://euvd.enisa.europa.eu/vulnerability/CVE-2021-22941) is an improper access control vulnerability in Citrix ShareFile storage zones controller that could allow unauthenticated remote compromise.

CrowdSec has been tracking this vulnerability and its exploits since 15th of December 2023.

CrowdSec network observations suggest that most exploitation of CVE-2021-22941 involves focused reconnaissance to identify viable targets. Attackers typically tailor their campaigns based on system exposure and configuration. It is unlikely that a given attack is accidental.
CrowdSec network telemetry also shows that exploitation of CVE-2021-22941 has significantly declined over the past week. Attack volumes are well below the long-term average, suggesting attackers are rapidly losing interest. The vulnerability appears to be falling out of active use across most threat landscapes.

Attempts to exploit this vulnerability often involve requests to endpoints containing `/upload.aspx`.

## Timeline

- 2021-09-23: CVE Published. CVE-2021-22941 is published to NVD.
- 2022-03-25: CISA KEV. CVE-2021-22941 is added to the Known Exploited Vulnerabilities catalog by CISA.
- 2022-04-15: CISA Remediation Deadline. Expiration of the CISA remediation deadline as described in [BOD 22-01](https://www.cisa.gov/news-events/directives/bod-22-01-reducing-significant-risk-known-exploited-vulnerabilities).
- 2023-12-15: Rule Released. CrowdSec releases a rule to detect CVE-2021-22941 exploitation attempts against the CrowdSec Network.
- 2024-11-23: CrowdSec First Seen. CrowdSec observes in-the-wild exploitation of CVE-2021-22941 for the first time.

## References

- https://nvd.nist.gov/vuln/detail/CVE-2021-22941
- https://github.com/hoavt18/CVE-2021-22941

## Live exploitation data

The [Live Exploit Tracker page](https://tracker.crowdsec.net/cves/CVE-2021-22941) follows observed exploitation activity for CVE-2021-22941. [Request an API key](https://tracker.crowdsec.net/request-api-key) for full access to its exploitation timeline, attacking IP addresses and blocklists.