Citrix Patches Critical Authentication Bypass in NetScaler ADC and Gateway
Updates address two security flaws, including a critical-severity authentication bypass affecting customer-managed deployments.
Key Takeaways
- Citrix released updates for two security flaws in NetScaler ADC and NetScaler Gateway, including a critical authentication bypass.
- The vulnerabilities affect customer-managed deployments, including certain FIPS and NDcPP builds, and SecurAccess.
- No CVE identifiers or public exploit details were provided; active exploitation has not been confirmed.
- Organizations should apply the updates immediately, especially for internet-facing systems.
Quick answers
- What happened?
- Citrix has released security updates to address two vulnerabilities in NetScaler ADC and NetScaler Gateway, including a critical-severity authentication bypass. The flaws affect customer-managed deployments, including certain FIPS and NDcPP builds, as well as SecurAccess. Organizations are urged to apply the patches immediately.
- Which products are affected?
- NetScaler ADC, NetScaler Gateway
- What should defenders do?
- Apply the latest updates from Citrix immediately. Review the official advisory for specific version information and ensure all affected systems are patched. Monitor for any unusual activity on NetScaler devices.
Citrix has released updates to address two security flaws impacting NetScaler ADC and NetScaler Gateway deployments, including a critical-severity authentication bypass vulnerability. The issues affect customer-managed NetScaler ADC and NetScaler Gateway, including certain FIPS and NDcPP builds, as well as SecurAccess.
The authentication bypass vulnerability is rated critical severity, as it could allow an attacker to bypass authentication mechanisms and gain unauthorized access to sensitive resources or administrative functions. The exact impact depends on the specific configuration and deployment. A second security flaw was also addressed, though details are limited.
Citrix has not provided CVE identifiers in the advisory, and no public exploit details or reports of active exploitation in the wild have been confirmed. The company advises customers to apply the updates immediately to mitigate the risk.
Organizations running affected versions of NetScaler ADC or NetScaler Gateway should prioritize patching, especially for internet-facing deployments. As with any critical authentication bypass, the potential for unauthorized access makes timely remediation essential.
Security Details
A critical-severity authentication bypass vulnerability exists in NetScaler ADC and NetScaler Gateway, affecting customer-managed deployments including certain FIPS and NDcPP builds, and SecurAccess. Successful exploitation could allow an attacker to bypass authentication and gain unauthorized access to sensitive resources or administrative functions. A second security flaw was also patched, but details are limited. No CVE identifiers or public exploit details were provided.
Affected products
NetScaler ADC, NetScaler Gateway
Mitigation
Apply the latest updates from Citrix immediately. Review the official advisory for specific version information and ensure all affected systems are patched. Monitor for any unusual activity on NetScaler devices.
Sources
The Hacker News
Critical NetScaler Flaw Can Bypass Authentication on Certain Gateway and AAA Servers
Aug 20, 2026 · 13:35
Original link
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