Actively exploited · Published Mar 23, 2026 · Assigned by NetScaler

CVE-2026-3055Insufficient input validation leading to memory overread

Critical 9.3 Exploited

In plain English

A critical-severity out-of-bounds read in ADC from NetScaler. Attackers are actively exploiting it in the wild (listed by CISA on March 30, 2026). The chance it is exploited in the next 30 days is estimated at 91.5% (higher than 99.8% of all known vulnerabilities). Ready-made attack tooling exists: Metasploit, Nuclei, public proof-of-concept code. Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Severity (CVSS 4.0)9.3Critical
Exploit odds (30 days)91.5%top 0.2% of all CVEs
Exploited in the wildYesCISA KEV since Mar 30, 2026
Attack tooling3Metasploit, Nuclei, Public PoC

CISA guidance

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Federal agencies must remediate by Apr 2, 2026.

Official description

Insufficient input validation in NetScaler ADC and NetScaler Gateway when configured as a SAML IDP leading to memory overread

Affected products (as reported)

VendorProductVersions
NetScaler ADC 14.1 – before 66.5913.1 – before 62.2313.1 FIPS and NDcPP – before 37.262
NetScaler Gateway 14.1 – before 66.5913.1 – before 62.23

Weakness: CWE-125 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L

References