# CVE-2019-13608: Citrix StoreFront - XXE

> Live exploitation tracking for CVE-2019-13608 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-2019-13608

## Key facts

- **Exploitation phase:** Limited Exploitation. The vulnerability is known but shows very limited attacker interest or exploitation activity.
- **CVSS score:** 7.5
- **Public exploit available:** Yes
- **Affected products:** Citrix StoreFront
- **Weaknesses:** CWE-611 (Improper Restriction of XML External Entity Reference)
- **Tags:** enterprise_software

## Description

Citrix StoreFront Server before 1903, 7.15 LTSR before CU4 (3.12.4000), and 7.6 LTSR before CU8 (3.0.8000) allows XXE attacks.

## CrowdSec analysis

[CVE-2019-13608](https://euvd.enisa.europa.eu/vulnerability/CVE-2019-13608) is an XML External Entity (XXE) vulnerability in Citrix StoreFront Server versions prior to 1903, 7.15 LTSR before CU4, and 7.6 LTSR before CU8. This flaw could allow remote attackers to exploit XML parsing to access sensitive information from the affected server, potentially leading to data disclosure.

CrowdSec has been tracking this vulnerability and its exploits since 18th of February 2026.

Insights from the CrowdSec network reveal that the attackers trying to exploit CVE-2019-13608 are composed of a fairly even mix of opportunistic and targeted actors. Some attackers employ preliminary reconnaissance, while others use indiscriminate scanning.
In addition, according to the CrowdSec network, attack volume against CVE-2019-13608 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.

Attackers exploit this vulnerability by sending crafted XML payloads to the `/Citrix/StoreAuth/ExplicitForms/Start` endpoint, attempting to trigger XML External Entity (XXE) processing on Citrix StoreFront servers.

## Timeline

- 2019-08-29: CVE Published. CVE-2019-13608 is published to NVD.
- 2021-11-03: CISA KEV. CVE-2019-13608 is added to the Known Exploited Vulnerabilities catalog by CISA.
- 2022-05-03: 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).
- 2026-02-18: Rule Released. CrowdSec releases a rule to detect CVE-2019-13608 exploitation attempts against the CrowdSec Network.
- 2026-02-20: CrowdSec First Seen. CrowdSec observes in-the-wild exploitation of CVE-2019-13608 for the first time.

## References

- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-13608
- https://support.citrix.com/article/CTX251988
- https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2019/CVE-2019-13608.yaml

## Live exploitation data

The [Live Exploit Tracker page](https://tracker.crowdsec.net/cves/CVE-2019-13608) follows observed exploitation activity for CVE-2019-13608. [Request an API key](https://tracker.crowdsec.net/request-api-key) for full access to its exploitation timeline, attacking IP addresses and blocklists.