Exploited vulnerability · CISA KEV

Is CVE-2019-13608 exploited? Yes: in CISA KEV since 3 Nov 2021

Gociux · Citrix StoreFront Server · data: CISA KEV, CVE record, FIRST EPSS

Yes. CVE-2019-13608, Citrix StoreFront Server XML External Entity (XXE) Processing Vulnerability, is being exploited in the wild. CISA added it to its Known Exploited Vulnerabilities catalog on 3 Nov 2021, 797 days after it was published. It is known to be used in ransomware campaigns. It affects Citrix StoreFront Server, an internet-facing product of the kind attackers use for initial access. If you run it, CISA's required action is: Apply updates per vendor instructions.

What it is

Citrix StoreFront Server contains an XML External Entity (XXE) processing vulnerability that may allow an unauthenticated attacker to retrieve potentially sensitive information.

What to do

1. Check whether you run it. Look for StoreFront Server in your asset inventory, including appliances and cloud images. Stack check lists every exploited Citrix CVE at once.
2. Apply the fix. Apply updates per vendor instructions.
3. If you can't patch today, take the affected service off the internet or restrict who can reach it, and check its logs for signs of compromise since 29 Aug 2019.
4. Get told next time. Email alerts when CISA adds a CVE for Citrix.

References

• nvd.nist.gov/vuln/detail/CVE-2019-13608

Sources: CISA KEV (exploitation, ransomware use, required action, due date), the CVE record (publication date, CVSS, CNA), NVD and FIRST EPSS (live score). More: all KEV additions in November 2021 · Citrix scorecard · act-now radar.