Citrix NetScaler DoS flaw patched
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Citrix fixed an out-of-bounds write in NetScaler ADC/Gateway that can cause a Denial of Service; no exploitation reported.
NCSC-NL published an advisory covering CVE-2026-88779, a memory overflow (out-of-bounds write) vulnerability affecting Citrix NetScaler ADC and NetScaler Gateway versions prior to 14.1-73.41 and 13.1-64.28. The vulnerability can be exploited to disrupt normal service availability, resulting in a Denial of Service condition. The CVSS v4 score is listed as 8.7, indicating significant impact if triggered.
Citrix has released updated versions that address the issue. Defenders running NetScaler ADC or Gateway should verify their deployed version against the fixed releases (14.1-73.41 or 13.1-64.28 and later) and apply patches as soon as feasible given the availability impact and the history of NetScaler products being targeted by threat actors. No indication of active exploitation is provided in this advisory.
Mentioned in this report
Source reporting: https://advisories.ncsc.nl/2026/ncsc-2026-0399.html
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