Citrix ShareFile Improper Access Control Vulnerability

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.

CheckOps priority index

8.5/10 Patch within 24 h

Severity9.8

Probability5.4

Exploitation5/5

Severity = CVSS. Probability = EPSS (FIRST). Exploitation = public signals: KEV, EUVD, ransomware, EPSS above 10 %, no account required.

EPSS · today 53.6% higher than 99.0% of CVEs

CVSS 3.1 9.8 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:

Exploited for 1,684 days 25 Mar 2022

CISA due date 15 Apr 2022 for US federal agencies

Exploitation probability EPSS · FIRST

EPSS probability (%)Percentile among all CVEs

Exploitation signals 5 / 5

KEV catalog (CISA)25 Mar 2022
Exploited in EUVD (ENISA)25 Mar 2022
Used by ransomwareyes
EPSS above 10 %53.6%
No account, over the networkyes

What to do

Fix

Apply the vendor’s fix as soon as it is available.

CISA guidance: Apply updates per vendor instructions.

Meanwhile

Take the service off the internet or restrict access to it, watch the logs and look for signs of compromise.

Manufacturers (CRA)

Exploited vulnerability in your product: early warning to ENISA within 24 h, then notification within 72 h (Article 14 of the Cyber Resilience Act). The CRA explained

Affected products

Citrix ShareFile Storage Zones ControllerShareFile

Affected versions

5.11.20

Weaknesses (CWE)

CWE-284

Open source packages OSV

Affected libraries according to OSV, with fixed versions.

Timeline

23 Sept 2021
Published
25 Mar 2022
Exploitation reported (ENISA)
25 Mar 2022
Added to the KEV catalog
15 Apr 2022
CISA remediation due date
26 Sept 2026
EPSS peak: 53.6%

References

Other exploited vulnerabilities from the same vendor

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