Affects widely-used Citrix NetScaler ADC/Gateway (SAML IDP) with high-severity memory overread risk; potential for DoS or info disclosure across many deployments.
CVE-2026-3055
Memory overread in NetScaler ADC/Gateway when used as SAML IDP.
Is CVE-2026-3055 being exploited?
Yes. CVE-2026-3055 appears in CISA's Known Exploited Vulnerabilities catalog, which means exploitation in the wild has been confirmed and reported. Treat it as active rather than theoretical, and patch it ahead of higher-scoring vulnerabilities that carry no exploitation evidence.
How severe is CVE-2026-3055?
CVE-2026-3055 is rated Critical with a CVSS score of 9.3. 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-2026-3055?
Yes. A fix has been recorded for CVE-2026-3055. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-3055 affect?
CVE-2026-3055 affects Citrix NetScaler ADC, Citrix NetScaler Gateway. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-3055?
Patch when released; apply mitigations and monitor.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Memory overread via malformed SAML IDP inputs; possible crash and information disclosure.
Patch when possible
- affected>= 14.1 and < 66.59
- affected>= 13.1 and < 62.23
- affected>= 13.1 FIPS and NDcPP and < 37.262
- affected>= 14.1 and < 66.59
- affected>= 13.1 and < 62.23
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.