Citrix NetScaler ADC/Gateway are widely deployed enterprise network appliances; a DoS against these perimeter devices can disrupt access and services across organizations.
CVE-2026-88777
Memory overflow in Citrix NetScaler ADC/Gateway enabling remote DoS
Is CVE-2026-88777 being exploited?
Not confirmed. CVE-2026-88777 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked.
How severe is CVE-2026-88777?
CVE-2026-88777 is rated High with a CVSS score of 8.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-88777?
Yes. A fix has been recorded for CVE-2026-88777. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-88777 affect?
CVE-2026-88777 affects Citrix NetScaler ADC < 14.1-73.37, Citrix NetScaler ADC < 13.1-64.23, ADC FIPS < 14.1-73.37 FIPS, ADC FIPS < 13.1.37.279 FIPS and NDcPP, and 2 further products or versions. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-88777?
Apply Citrix updates to 14.1-73.37 / 13.1-64.23 or later immediately
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote memory overflow can crash or cause unpredictable behavior in NetScaler ADC/Gateway, resulting in denial of service to applications and users.
Immediate action required
- affected< 14.1-73.37
- affected< 13.1-64.23
- affected< 14.1-73.37 FIPS
- affected< 13.1.37.279 FIPS and NDcPP
- affected< 14.1-73.37
- affected< 13.1-64.23
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.