Is itCheck something

No. CVE-2026-88771

Attackers can run commands on Citrix NetScaler before login

Being used now

Yes. Attackers are using this right now.

Companies using Citrix NetScaler ADC or Gateway, including default setups.

What to do

Update NetScaler using Citrix's bulletin. If you may be hit, investigate as well.

Confirmed in attacksSep 27, 2026
ProductCitrix NetScaler
GitHub repos6
Attack likelihood, next 30 days82%

Attack likelihood is EPSS, a daily estimate from FIRST.org of how likely this bug is to be used in attacks in the next 30 days.

The official description

Citrix NetScaler ADC and NetScaler Gateway contain an improper input validation vulnerability that could allow an unauthenticated attacker to execute arbitrary commands.

For your tech helper or AI assistant

A read-only checklist. Paste it into Claude, ChatGPT or a coding agent; it only looks and changes nothing.

Read-only check, change nothing, send nothing anywhere.
Is Citrix NetScaler (CVE-2026-88771) installed or running on this machine or in this project?
1. Find every copy and its version (apps, packages, containers, lockfiles).
2. Compare each version against the vendor's fixed version for CVE-2026-88771. Quote the vendor page you used.
3. Report a table: where, version, fixed version, status (exposed / fixed / not installed / unsure).
4. List the exact update steps, but do not run them.
Download playbook (.md)

Code on GitHub

Repos named after this bug. Some are scanners or write-ups, some are working attack code. Do not run them on a machine you care about.

Sources