# CVE-2017-5573: Citrix XenServer authorization bypass in xapi

Source: https://junglewise.ai/threats/cve-2017-5573-citrix-xenserver-authorization-bypass-in-xapi  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2017-01-30. Updated: 2026-05-13  
License: CC BY 4.0 with a link back

CVE-2017-5573 · Severity: medium · CVSS 4.9 · Published 2017-01-30

A vulnerability in Citrix XenServer allows a user with restricted 'read-only' administrative access to cancel ongoing tasks initiated by other administrators. This could lead to operational disruptions or the intentional interruption of critical system maintenance and management activities. The issue affects the xapi component in versions up to and including 7.0.

Technologies: [Citrix Xenserver](https://junglewise.ai/threats/technologies/xenserver). Vendors: [Citrix](https://junglewise.ai/threats/vendors/citrix).

## Quick answers

**Is CVE-2017-5573 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2017-5573 being exploited in the wild.

**How severe is CVE-2017-5573?** Medium severity, with a CVSS score of 4.9, published 30 January 2017.

**Which products and versions are affected?** Citrix Xenserver through 7.0.

**Is there a fix for CVE-2017-5573?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2017-5573 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2017-5573?** Check whether you run Citrix Xenserver at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

An authorization bypass vulnerability exists in the Linux Foundation xapi (Xen API) component of Citrix XenServer. The flaw allows an authenticated user with high-privilege but 'read-only' permissions to perform actions beyond their intended scope, specifically the cancellation of tasks managed by other administrative accounts. The vulnerability is reachable over the network and requires valid administrative credentials. Successful exploitation impacts the integrity of system operations by allowing unauthorized control over task lifecycles. Citrix has addressed this in security bulletin CTX220112.

## Affected products

- Citrix XenServer through 7.0

## Timeline

- 2017-01-30: disclosed
- 2017-01-30: advisory: NVD publication date

## References

- [http://www.securityfocus.com/bid/95796](http://www.securityfocus.com/bid/95796)
- [http://www.securitytracker.com/id/1037716](http://www.securitytracker.com/id/1037716)
- [https://support.citrix.com/article/CTX220112](https://support.citrix.com/article/CTX220112)

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