overview

CVE-2025-7775 is a critical memory overflow vulnerability in Citrix NetScaler ADC and NetScaler Gateway that enables unauthenticated remote code execution (RCE) and/or denial of service (DoS). The vulnerability is being actively exploited and poses severe risks—particularly to organizations in the retail, healthcare, and financial sectors.

Vulnerability Description

CVE-2025-7775 impacts Citrix NetScaler ADC and Gateway appliances when configured with:

  • Gateway or AAA virtual servers
  • Certain load balancing virtual servers with IPv6/DBS IPv6 services
  • CR virtual servers of type HDX

Exploitation allows a remote, unauthenticated attacker to execute arbitrary code on the device or cause a system crash, resulting in Denial of Service.

Potential Impact

  • Unauthorized remote code execution (full compromise)
  • Denial of Service (service outage/disruption)
  • Persistent backdoors (web shell deployment or stealthy access—sometimes surviving patching)
  • Broad impact on critical industries, but risk extends to any organization with affected NetScaler devices

Attack Vector & Exploitation

  • Attackers exploit this vulnerability remotely, without authentication.
  • Appliances must be configured in a vulnerable virtual server mode.
  • While the attack complexity is high (due to challenges in exploiting memory corruption), active exploitation is confirmed.
  • Threat actors have deployed persistent access mechanisms, remaining through some patching cycles.

 

 

affected products and versions

  • Citrix NetScaler ADC
  • Citrix NetScaler Gateway

Vulnerable Versions:

  • 1 — prior to 14.1-47.48
  • 1 — prior to 13.1-59.22
  • 1-FIPS and NDcPP — prior to 13.1-37.241-FIPS/NDcPP
  • 1-FIPS and NDcPP — prior to 12.1-55.330-FIPS/NDcPP

Patched Versions:

  • 1-47.48 and above
  • 1-59.22 and above
  • 1-37.241-FIPS/NDcPP and above
  • 1-55.330-FIPS/NDcPP and above

 

 

Threat status

  • Exploited in the wild: Exploitation began before patch release.
  • Observed incidents: Deployment of persistent backdoors/web shells, often leaving over 28,000 unpatched appliances
  • Techniques: Remote code execution for persistence or lateral movement; Denial of Service for disruption.
  • Targeted industries: Primarily retail, healthcare, financial; all sectors using NetScaler at risk.
  • Proof of Concept (PoC): No known public exploit yet, but intelligence sources expect rapid emergence.

 

 

INDICATORS OF COMPROMISE (IOCS)

Currently, there are no confirmed, publicly disclosed IOCs specifically tied to successful CVE-2025-7775 exploitation. Neither Citrix nor research teams have released related IP addresses, domain names, file hashes, or malware signatures.

Forensic and Monitoring Insights

  • Ongoing investigations continue across research, threat intel, and Citrix teams to identify relevant IOCs.
  • Exploitation may leave web shells or result in repeated malformed requests to NetScaler endpoints, but no detailed forensic artifacts have been published.
  • Avertium actively monitors and will disclose IOCs as soon as they are located.

Where to Monitor IOC Updates

  • Citrix official security advisories
  • SOC Prime Platform global threats feed
  • Industry news outlets (e.g., BleepingComputer)
  • Threat intelligence providers like Arctic Wolf and Rapid7

For direct Avertium support, contact your Service Delivery Manager or Account Executive.

 

 

MITRE ATT&CK ttPS

Below are key MITRE ATT&CK tactics and techniques associated with exploitation of CVE-2025-7775, based on vulnerability nature and typical attack behaviors:

Initial Access

  • T1190 — Exploit Public-Facing Application:
    Memory overflow on NetScaler allows attackers to gain initial, unauthenticated access through exposed services.

Execution

  • T1059 — Command and Scripting Interpreter:
    After exploiting, attackers may execute arbitrary commands via shell/scripting interpreters.
  • T1203 — Exploitation for Client Execution:
    Forced execution of malicious payloads directly on the target device.

Persistence

  • T1546 — Event Triggered Execution:
    Use of scheduled tasks, cron jobs, or startup scripts for persistence.
  • T1053 — Scheduled Task/Job:
    If possible, attackers install scheduled jobs to maintain access post-reboot or patch.

Privilege Escalation

  • T1068 — Exploitation for Privilege Escalation:
    If compromise occurs under limited privileges, further exploits may seek system/root access.

Defense Evasion

  • T1218 — System Binary Proxy Execution:
    Abuse of Citrix-native binaries or libraries to evade detection.
  • T1140 — Deobfuscate/Decode Files or Information:
    Payloads may be encoded to bypass monitoring.

Impact

  • T1499 — Endpoint Denial of Service:
    Exploit can directly crash devices or applications, disrupting services.
  • T1485 — Data Destruction:
    Attackers could corrupt or delete configurations, causing service outages.

For SIEM integration, detection guidance, and further triage, platforms like SOC Prime provide ATT&CK-mapped analytic rules.

 

 

additional Recommendations + information

Immediate Mitigation Measures

  • Apply Citrix patches immediately:
    Upgrade to the latest patched versions:
    • 1-47.48+
    • 1-59.22+
    • 1-FIPS/NDcPP 13.1-37.241+
    • 1-FIPS/NDcPP 12.1-55.330+
  • Restrict internet exposure:
    Shield exposed virtual servers (Gateway, VPN, LB) behind firewalls when possible.
  • Limit Gateway/AAA functionality:
    Disable or restrict features to necessary internal users only.
  • Review IPv6 bindings:
    Disable unused IPv6 support, especially for external access.
  • Protect admin interfaces:
    Segment management interfaces from untrusted networks; use strong authentication.

Patch and System Monitoring

  • Monitor vendor advisories:
    Keep tracking Citrix releases for fixes and emergent mitigation steps.
  • Network monitoring:
    Deploy sensors to detect signs of exploitation or anomalous traffic, including backdoor/persistent access attempts.
  • SIEM integration:
    Ingest NetScaler logs for real-time alerting and forensic review.

Network Security Enhancements

  • Block malicious IPs:
    Use threat intelligence (Shadowserver, CISA) to block known attacker infrastructure.
  • Intrusion detection/prevention:
    Enable IDS/IPS rules for Citrix vulnerabilities.
  • Isolate vulnerable assets:
    Segment unpatched appliances; restrict external connectivity.
  • Run continuous vulnerability scans:
    Proactively identify and remediate unpatched systems.
  • Hunt for abuse artifacts:
    Look for new accounts/configuration changes indicating persistent attacker footholds.

 

 

ADDITIONAL SERVICE OFFERINGS


Avertium offers specialized services to help organizations rapidly defend against and recover from attacks like those exploiting CVE-2025-7775:

  • Threat Detection & Response (TDR):
    Proactive detection and XDR-informed response for vulnerabilities like CVE-2025-7775. Quickly identifies exploit attempts, maps them to MITRE ATT&CK, and provides rapid containment and remediation to strengthen resilience.

  • Security Information and Event Management (SIEM):
    Centralized monitoring and alerting for anomalous Citrix activity. SIEM enables detection of lateral movement, data exfiltration, and compliance reporting by aggregating NetScaler logs and automating incident response.

  • Cybersecurity Strategy Services:
    Aligns organizational risk management with frameworks like MITRE ATT&CK, providing:
    • Strategic Security Assessments: Identify exposure to memory overflow attacks and create targeted mitigation plans.
    • Threat Mapping: Relate real-world threats to your environment and prioritize remediation.
    • Cyber Maturity Roadmap: Build policies and resilience strategies for business continuity during critical incidents.
  • Attack Surface Management (ASM):
    Routine identification, prioritization, and mitigation of vulnerabilities in internet-facing services, including Citrix. ASM limits opportunity for unauthenticated exploitation and enhances defensive posture.

  • Governance, Risk, and Compliance (GRC):
    Expertise in aligning with regulations (PCI DSS, HIPAA, GDPR). Provides audits, incident response capability, and documentation to satisfy compliance requirements in at-risk sectors.

  • Security Operations Center (SOC) – Guadalajara, Mexico:
    Regional, 24/7 threat monitoring and rapid incident handling for Latin America and global clients—improving time-to-detection and minimizing harmful impacts from NetScaler vulnerabilities.


 

 

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