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.
Conclusion & alert: CVE-2019-13608 is rated Critical Active Threat (90/100): CVSS High severity, with high exploitation likelihood (EPSS 71.67%, 99th percentile). Core evidence: CISA KEV confirms active exploitation (added 2021-11-03) affecting Citrix / StoreFront Server. a weakness (CWE-611) Unauthenticated remote administrative access may be possible. Mandatory action: The CISA remediation deadline has passed—treat as an emergency patch priority.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
: Citrix StoreFront Server XML External Entity (XXE) Processing Vulnerability · CISA KEV detail
: 2021-11-03
: 2022-05-03
: Apply updates per vendor instructions.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-06 | 71.25% | 71.67% | +0.41% |
| 2 | 2026-04-15 | 71.36% | 71.25% | -0.10% |
| 3 | 2026-03-17 | — | 71.36% | — |
Full EPSS history (20 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | [email protected] |
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
| 5.0 | 2.0 | MEDIUM |
|
10.0 | 2.9 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| citrix | storefront_server | >= 1811, < 1903 | cpe:2.3:a:citrix:storefront_server:*:*:*:*:*:*:*:* |
| citrix | storefront_server | < 3.12.4000 | cpe:2.3:a:citrix:storefront_server:*:*:*:*:*:*:*:* |
| citrix | storefront_server | < 3.0.8000 | cpe:2.3:a:citrix:storefront_server:*:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://support.citrix.com/article/CTX251988 | Mitigation Vendor Advisory |
| https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-13608 | US Government Resource |