Citrix NetScaler ADC: memory corruption

Citrix NetScaler ADC

Memory overflow vulnerability vulnerability in Citrix NetScaler ADC and Citrix NetScaler Gateway. This issue affects ADC: before 14.1-73.37, before 13.1-64.23, before 14.1-73.37 FIPS, and before 13.1.37.279 FIPS and NDcPP; Gateway: before 14.1-73.37 and before 13.1-64.23 leading to unpredictable or erroneous behavior or Denial of Service

Do this now

Restrict internet exposure of NetScaler ADC and Gateway and watch for a vendor fix.

First seen: 24 Oct 2026
Last update: 24 Oct 2026, 00:17 UTC
Identifiers: CVE-2026-88773
CVE-2026-88775
CVE-2026-88776
CVE-2026-88777
CVSS: 9.8
Source: news
On the menu as: VPN & firewalls

Check this repository for exposure to one security incident from pwned.coffee. Report first, change nothing until I say so.

## Citrix NetScaler ADC: memory corruption
Severity: critical. Patch status: fix status unknown.
Affected: Citrix NetScaler ADC
Ids: CVE-2026-88773, CVE-2026-88775, CVE-2026-88776, CVE-2026-88777

Memory overflow vulnerability vulnerability in Citrix NetScaler ADC and Citrix NetScaler Gateway. This issue affects ADC: before 14.1-73.37, before 13.1-64.23, before 14.1-73.37 FIPS, and before 13.1.37.279 FIPS and NDcPP; Gateway: before 14.1-73.37 and before 13.1-64.23 leading to unpredictable or erroneous behavior or Denial of Service

## Steps
1. This touches infrastructure (vpn-edge). Look in terraform, ansible, cloud-init, Dockerfiles and docs for the product and version we run. If it isn't in the repo, say so and list what a human should check on the box.
2. There is no fix yet. Until one ships: Memory overflow vulnerability vulnerability in Citrix NetScaler ADC and Citrix NetScaler Gateway. This issue affects ADC: before 14.1-73.37, before 13.1-64.23, before 14.1-73.37 FIPS, and before 13.1.37.279 FIPS and NDcPP; Gateway: before 14.1-73.37 and before 13.1-64.23 leading to unpredictable or erroneous behavior or Denial of Service

## Report
A table: file, product or package, version in use, affected yes/no, exact fix. Then anything a human has to check outside the repo.

If you have the pwned.coffee MCP server (https://pwned.coffee/mcp), call lookup_cve("CVE-2026-88773") for the latest, and check_repo with this repo's lockfiles, Dockerfiles and workflows for a full receipt.
Sources: https://nvd.nist.gov/vuln/detail/CVE-2026-88777 https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX697096&articleTitle=Citrix_NetScaler_ADC_and_Citrix_NetScaler_Gateway_Security_Bulletin_for_CVE_2026_88771_CVE_2026_88772_CVE_2026_88773_CVE_2026_88774_CVE_2026_88775_CVE_2026_88776_CVE_2026_88777_and_CVE_2026_88778 https://nvd.nist.gov/vuln/detail/CVE-2026-88776 https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX697096 https://nvd.nist.gov/vuln/detail/CVE-2026-88775 https://nvd.nist.gov/vuln/detail/CVE-2026-88773
https://pwned.coffee/i/citrix-netscaler-adc-memory-corruption-cve-2026-88777

Timeline

24 Oct 2026, 01:17 UTC
Proof-of-concept code for CVE-2026-88773 is public on GitHub. Unverified, but expect scanning to follow.
24 Oct 2026, 01:17 UTC
Proof-of-concept code for CVE-2026-88775 is public on GitHub. Unverified, but expect scanning to follow.
24 Oct 2026, 00:17 UTC
Proof-of-concept code for CVE-2026-88776 is public on GitHub. Unverified, but expect scanning to follow.
24 Oct 2026, 00:17 UTC
Proof-of-concept code for CVE-2026-88777 is public on GitHub. Unverified, but expect scanning to follow.
24 Oct 2026
First reported.

Sources

Totalone very hot coffee