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  3. CVE-2026-88772
Exploited in the wildVPNs, firewalls & gatewaysWork IT

CVE-2026-88772 Citrix NetScaler: memory-safety flaw

In plain words: The program mishandles the memory it uses to keep track of data. A specially made input can scramble that memory. Usually lets an attacker crash the program or run their own code with its permissions.

Confirmed exploited by CISA on · US federal patch deadline Sep 30, 2026

What to do

  1. Install Citrix's security update for NetScaler. If no update exists, follow the vendor's workaround or stop using the product until one ships.
  2. Patch edge devices first — attackers often start scanning for them within hours of a fix.
  3. Never expose the device's admin page to the internet.
  4. After patching a device that was exposed, follow the vendor's compromise checks, end active sessions and change passwords.

Read Citrix's advisory ↗

Who is affected

Work IT. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.

What's at risk: They face the internet and guard the whole network, so a flaw here can hand attackers a way in — and these devices usually run no antivirus, so break-ins go unnoticed.

The details

Official name
Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability
Product
Citrix NetScaler
CISA description
Citrix NetScaler ADC and NetScaler Gateway contain an improper restriction of operations within the bounds of a memory buffer vulnerability that could allow for remote code execution or denial of service
Type of flaw
Memory-safety flaw (CWE-119)
Confirmed exploited
Sep 27, 2026
US federal patch deadline
Sep 30, 2026

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Answering about CVE-2026-88772 ·

Questions about CVE-2026-88772

Is CVE-2026-88772 being exploited?

Yes. CISA added CVE-2026-88772 to its Known Exploited Vulnerabilities catalog on Sep 27, 2026, which means there is reliable evidence of real-world attacks.

How do I fix CVE-2026-88772?

Install Citrix's security update for NetScaler. If no update exists, follow the vendor's workaround or stop using the product until one ships. Patch edge devices first — attackers often start scanning for them within hours of a fix.

Am I affected by CVE-2026-88772?

Only if you use Citrix NetScaler. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.

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