Exploitation timeline
Threadlinqs has recorded 9 NetScaler CVEs published between and . The busiest month was 2026-06 (6 new CVEs). 1 of them (11%) are listed in CISA KEV, which means exploitation in the wild has been confirmed.
Most exploited vulnerabilities
Ranked with CISA KEV listings first, then EPSS exploit probability, then CVSS score. Showing 9 of 9 tracked NetScaler CVEs.
- CVE-2026-19490critical 9.8KEVEPSS 7%
- CVE-2025-12101medium 5.9EPSS 25.1%
- CVE-2026-8451high 7.5EPSS 0.5%
- CVE-2026-8452critical 9.8EPSS 0.5%
- CVE-2026-8655critical 9.8EPSS 0.5%
- CVE-2026-10817high 7.5EPSS 0.4%
- CVE-2026-13474high 7.5EPSS 0.4%
- CVE-2026-10816high 7.5EPSS 0.2%
- CVE-2026-19489high 8.8
Products affected
Threadlinqs normalises CPE and CNA product records across all 9 CVEs; 2 distinct NetScaler products are affected. The most frequently affected:
- ADC 9 CVEs
- Gateway 9 CVEs
Threat activity
4 tracked threat campaigns reference NetScaler products or exploit NetScaler CVEs:
- CVE-2026-19490 — Critical Authentication Bypass in Citrix NetScaler ADC and Gateway (CVSS 9.3) with Accompanying CVE-2026-19489 Memory Overflow (CVSS 8.8)CRITICAL
- CitrixBleed-Class NetScaler ADC/Gateway SAML AuthnRequest Memory Disclosure (CVE-2026-8451) Exploited Within 24 Hours of DisclosureCRITICAL
- CVE-2026-8451: Memory Overread in Citrix NetScaler ADC/Gateway SAML IdP ('CitrixBleed'-class, CVSS 8.8) — Exploited Within 24 Hours of DisclosureHIGH
- CitrixBleed 2.0: CVE-2026-8451 NetScaler SAML IDP Memory Overread Under Active ExploitationCRITICAL
How to prioritise NetScaler patching
This order follows the data Threadlinqs holds for NetScaler, not a generic severity checklist:
- 1 of 9 NetScaler CVEs (11%) are in CISA KEV: treat them as actively exploited and remediate them first, starting with CVE-2026-19490.
- Outside KEV, the highest EPSS scores are CVE-2025-12101 (25.1%), CVE-2026-8451 (0.5%), CVE-2026-8452 (0.5%).
- 3 CVEs score Critical and 5 High on CVSS v3 (maximum 9.8, average 8.2); sequence these after KEV and high-EPSS items.
- 3 CVEs have a public exploit or proof of concept recorded, which shortens the time from disclosure to attack.
About this data
Vendor attribution comes from the CNA and CPE product records of each CVE, folded to one vendor name; CVSS, EPSS and KEV status are read from the Threadlinqs CVE catalog; campaign and actor links come from tracked threat records. Counts reflect the data as of 2026-10-05 and refresh daily.