Critical Citrix Bleed 2 Flaw Actively Exploited in Cyber Attacks

TL;DR

A critical vulnerability in NetScaler ADC and Gateway, known as “Citrix Bleed 2” (CVE-2025-5777), is now believed to be actively exploited in attacks. Cybersecurity firm ReliaQuest reports an increase in suspicious sessions on Citrix devices. Organizations are urged to apply patches and strengthen their security measures to mitigate potential risks.

Introduction

Cybersecurity experts have raised alarms over a critical vulnerability in NetScaler ADC and Gateway, dubbed “Citrix Bleed 2” (CVE-2025-5777). Recent reports indicate that this flaw is now likely being exploited in real-world attacks. The cybersecurity firm ReliaQuest has observed a surge in suspicious sessions on Citrix devices, suggesting active exploitation¹.

Understanding Citrix Bleed 2

Citrix Bleed 2 is a severe vulnerability that affects NetScaler ADC and Gateway devices. This flaw, identified as CVE-2025-5777, can be exploited by attackers to gain unauthorized access to sensitive information and potentially take control of affected systems. The vulnerability poses a significant risk to organizations relying on Citrix technologies for secure remote access.

Evidence of Exploitation

ReliaQuest, a leading cybersecurity firm, has reported an increase in suspicious activities targeting Citrix devices. These activities include unusual network traffic patterns and unauthorized access attempts, which are indicative of active exploitation of the Citrix Bleed 2 vulnerability. The firm’s findings underscore the urgent need for organizations to address this security threat proactively¹.

Impact and Mitigation

The exploitation of Citrix Bleed 2 can have severe consequences, including data breaches, loss of sensitive information, and disruption of critical services. To mitigate the risks associated with this vulnerability, organizations are advised to:

• Apply Security Patches: Ensure that all Citrix NetScaler ADC and Gateway devices are updated with the latest security patches provided by Citrix.
• Monitor Network Traffic: Implement robust monitoring solutions to detect and respond to suspicious activities promptly.
• Strengthen Access Controls: Enforce strict access controls and authentication mechanisms to prevent unauthorized access.
• Conduct Regular Security Audits: Perform regular security audits and vulnerability assessments to identify and address potential security weaknesses.

Conclusion

The active exploitation of the Citrix Bleed 2 vulnerability highlights the critical importance of proactive cybersecurity measures. Organizations must remain vigilant and take immediate action to protect their systems from potential attacks. By applying security patches, monitoring network traffic, and strengthening access controls, businesses can significantly reduce the risks associated with this vulnerability.

Additional Resources

For further insights, check:

• BleepingComputer Article on Citrix Bleed 2

References

1. BleepingComputer (2025). “Citrix Bleed 2 Flaw Now Believed to Be Exploited in Attacks”. BleepingComputer. Retrieved 2025-06-27. ↩︎ ↩︎²