CVE-2026-3055

Citrix NetScaler memory corruption, confirmed exploited in the wild.

Citrix NetScaler ADC (formerly Citrix ADC), NetScaler Gateway (formerly Citrix Gateway) and NetScaler ADC FIPS and NDcPP contain an out-of-bounds reads vulnerability when configured as a SAML IDP leading to memory overread.

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91%chance of exploitation in the next 30 days (EPSS), 99th percentile

30 Maradded to CISA's Known Exploited Vulnerabilities list, 2026

2 Aprfederal remediation deadline, already passed

Passedpast the deadline: patch now

CISA's name for it	Citrix NetScaler Out-of-Bounds Read Vulnerability
Vendor and product	Citrix · NetScaler
Type	memory corruption · CWE-125
Exploited	Confirmed by CISA listed 30 March 2026
Likelihood	one of the most likely to be exploited of every vulnerability tracked
Deadline	2 April 2026 · already passed
Used in ransomware	Not reported
Advisories	support.citrix.com ↗ · nvd.nist.gov ↗

What to do

Three steps, in this order

Step 1

Update the product (and every browser or app that embeds it) to the fixed version.

Step 2

Make sure automatic updates are on and actually applied; restart where the update needs it.

Step 3

Watch endpoints for crashes and unusual child processes from the affected software.

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

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Questions

CVE-2026-3055 in short

Is CVE-2026-3055 being exploited?

Yes. CISA added CVE-2026-3055 to its Known Exploited Vulnerabilities catalogue on 30 March 2026, which it does only on evidence of exploitation in the wild.

What is the CISA deadline for CVE-2026-3055?

US federal agencies must remediate it by 2 April 2026. Everyone else should treat that date as the latest safe point to patch an internet-facing system.

How likely is CVE-2026-3055 to be exploited in the next 30 days?

FIRST's Exploit Prediction Scoring System gives it 91%, the 99th percentile of every CVE it scores.

How do I fix CVE-2026-3055?

Update the product (and every browser or app that embeds it) to the fixed version. Make sure automatic updates are on and actually applied; restart where the update needs it. Watch endpoints for crashes and unusual child processes from the affected software.

Same vendor

Other Citrix vulnerabilities being exploited

CVE	Product	Type	Listed
CVE-2026-88779	NetScaler	denial of service	4 October 2026
CVE-2026-88772	NetScaler	remote code execution	27 September 2026
CVE-2026-88771	NetScaler	exploited vulnerability	27 September 2026
CVE-2026-19490	NetScaler	authentication bypass	9 September 2026
CVE-2026-8452	NetScaler ADC and NetScaler Gateway	denial of service	26 August 2026

Sources: CISA Known Exploited Vulnerabilities catalogue (released 10 November 2026) and FIRST EPSS. Page compiled automatically by SAK T.L.M, the threat-intelligence tool of SAK T.E.C, on 13 November 2026.