Citrix NetScaler ADC und Gateway: Schwachstelle ermöglicht Denial of Service
WID-SEC-2026-3719 · first 05.10.2026 · updated 05.10.2026 · CVSS 7,5
What it is about
Citrix NetScaler ist eine integrierte Lösung für die Beschleunigung, das Traffic Management und die Sicherheit von Web-Applikationen. Citrix Access Gateway ist ein universell einsetzbares SSL-VPN. Advanced Access Control (AAC) ermöglichen es Administratoren, Zugriffsregeln für das Access Gateway festzulegen. Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Citrix Systems NetScaler ADC und Gateway ausnutzen, um einen Denial of Service Angriff durchzuführen.
Under what conditions?
Over the network and without logging in. This is the most dangerous combination: attackers can scan reachable devices automatically.
What can happen in the worst case
An attacker could use the vulnerability to
- einen Denial of Service Angriff durchzuführen
Am I affected?
Affected according to the BSI:
- Citrix Systems NetScaler ADC <14.1-73.41
- Citrix Systems NetScaler Gateway <14.1-73.41
- Citrix Systems NetScaler ADC <13.1-64.28
- Citrix Systems NetScaler Gateway <13.1-64.28
- Citrix Systems NetScaler ADC FIPS <14.1-73.41
- Citrix Systems NetScaler ADC FIPS <13.1-37.282
- Citrix Systems NetScaler ADC NDcPP <13.1-37.282
The installed version is usually shown under “Help → About” or in the device’s admin interface.
What helps?
Update to at least:
- Citrix Systems NetScaler ADC 14.1-73.41
- Citrix Systems NetScaler Gateway 14.1-73.41
- Citrix Systems NetScaler ADC 13.1-64.28
- Citrix Systems NetScaler Gateway 13.1-64.28
- Citrix Systems NetScaler ADC FIPS 14.1-73.41
- Citrix Systems NetScaler ADC FIPS 13.1-37.282
- Citrix Systems NetScaler ADC NDcPP 13.1-37.282
Is the vulnerability already being exploited?
- CVE-2026-88779: exploited in the wild according to CISA, in the catalogue since 04.10.2026.
Information and sources
- Original BSI advisory (WID)
- Citrix Security Advisory CTX697174 vom 2026-10-04 support.citrix.com
- CISA KEV: CVE-2026-88779 vom 2026-10-04 www.cisa.gov
CVE: CVE-2026-88779
Source: BSI warning and information service (CERT-Bund); CISA. The assessment of the conditions is my reading of the BSI text; the external pages are in their original language.