Exploited vulnerability · CISA KEV

Is CVE-2019-12991 exploited? Yes: in CISA KEV since 25 Mar 2022

Gociux · Citrix SD-WAN and NetScaler · data: CISA KEV, CVE record, FIRST EPSS

Yes. CVE-2019-12991, Citrix SD-WAN and NetScaler Command Injection Vulnerability, is being exploited in the wild. CISA added it to its Known Exploited Vulnerabilities catalog on 25 Mar 2022, 983 days after it was published. It affects Citrix SD-WAN and NetScaler, 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.

exploitedYesCISA KEV · 25 Mar 2022

ransomwareNot knownno confirmed use

EPSStop 1%among the most likely CVEs to be exploited

severity8.8CVSS 3.1 · high

US federal due15 Apr 2022BOD 22-01 deadline

What it is

Authenticated Command Injection in Citrix SD-WAN Appliance and NetScaler SD-WAN Appliance.

Vendor	Citrix (27 exploited CVEs in KEV)
Product	SD-WAN and NetScaler
Vulnerability	Citrix SD-WAN and NetScaler Command Injection Vulnerability
Weakness	CWE-78
Published	16 Jul 2019
Added to KEV	25 Mar 2022
Reported by (CNA)	mitre

What to do

Check whether you run it. Look for SD-WAN and NetScaler in your asset inventory, including appliances and cloud images. Stack check lists every exploited Citrix CVE at once.
Apply the fix. Apply updates per vendor instructions.
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 16 Jul 2019.
Get told next time. Email alerts when CISA adds a CVE for Citrix.

Other exploited CVEs in SD-WAN and NetScaler

CVE-2019-12989: Citrix SD-WAN and NetScaler SQL Injection Vulnerability (25 Mar 2022)

References

nvd.nist.gov/vuln/detail/CVE-2019-12991

Questions

Is CVE-2019-12991 being exploited?

Yes. CISA added CVE-2019-12991 to the Known Exploited Vulnerabilities catalog on 25 Mar 2022, which means there is reliable evidence of exploitation in the wild.

Is CVE-2019-12991 used in ransomware attacks?

CISA does not list known ransomware use for it. That can change, and exploitation alone is reason to fix it first.

How do I fix CVE-2019-12991?

Apply updates per vendor instructions. Check Citrix's advisory for the fixed versions, and if you can't patch quickly, restrict access to the affected SD-WAN and NetScaler and watch it for signs of compromise.

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 March 2022 · Citrix scorecard · act-now radar.

Running Citrix in a regulated environment?

We check exposure across your estate, patch or mitigate with your team, and set up detection for what attackers do after exploiting it.

Get in touch →