Exploited vulnerability · CISA KEV

Is CVE-2019-5544 exploited? Yes: in CISA KEV since 3 Nov 2021

Gociux · VMware ESXi and Horizon DaaS · data: CISA KEV, CVE record, FIRST EPSS

Yes. CVE-2019-5544, VMware ESXi and Horizon DaaS OpenSLP Heap-Based Buffer Overflow Vulnerability, is being exploited in the wild. CISA added it to its Known Exploited Vulnerabilities catalog on 3 Nov 2021, 698 days after it was published. It is known to be used in ransomware campaigns. It affects VMware ESXi and Horizon DaaS. If you run it, CISA's required action is: Apply updates per vendor instructions.

What it is

VMware ESXi and Horizon Desktop as a Service (DaaS) OpenSLP contains a heap-based buffer overflow vulnerability that allows an attacker with network access to port 427 to overwrite the heap of the OpenSLP service to perform remote code execution.

What to do

1. Check whether you run it. Look for VMware ESXi and Horizon DaaS in your asset inventory, including appliances and cloud images. Stack check lists every exploited VMware 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 6 Dec 2019.
4. Get told next time. Email alerts when CISA adds a CVE for VMware.

References

• nvd.nist.gov/vuln/detail/CVE-2019-5544

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 · VMware scorecard · act-now radar.