Memory Overread Vulnerability in NetScaler Management Interface by Citrix
CVE-2025-5777

9.3CRITICAL

Key Information:

Vendor

Netscaler

Vendor
CVE Published:
17 June 2025

Badges

🥇 Trended No. 1📈 Trended📈 Score: 12,100💰 Ransomware👾 Exploit Exists🟡 Public PoC🟣 EPSS 20%🦅 CISA Reported📰 News Worthy

What is CVE-2025-5777?

CVE-2025-5777 is a critical vulnerability identified in the NetScaler Management Interface, a product developed by Citrix that serves as an essential component for managing networking configurations, including secure gateway access for various applications. The vulnerability arises from insufficient input validation, which can lead to memory overread vulnerabilities when the NetScaler is configured as either a Gateway, such as for VPN or RDP Proxy services, or an AAA virtual server. This type of flaw poses significant risks as it could enable attackers to extract sensitive information from the memory, leading to potential exploitation of the system and unauthorized access to critical data, impacting the overall integrity and security of an organization’s network environment.

Potential impact of CVE-2025-5777

  1. Data Exposure: The memory overread vulnerability can expose sensitive data stored in memory, including authentication tokens, passwords, or other confidential information, leading to a higher risk of data breaches.

  2. Unauthorized Access: Exploiting this vulnerability may allow attackers to gain unauthorized access to the network and its resources, potentially compromising sensitive applications and data protected by the NetScaler interface.

  3. System Compromise: The ability to read memory contents may enable attackers to execute further exploits or enhance their control over affected systems, making it easier to deploy additional malware or ransomware, increasing the overall threat to the organization’s cybersecurity posture.

CISA has reported CVE-2025-5777

CISA provides regional cyber and physical services to support security and resilience across the United States. CISA monitor the most dangerious vulnerabilities and have identifed CVE-2025-5777 as being exploited but is not known by the CISA to be used in ransomware campaigns. This is subject to change at pace as recent news articles suggest the vulnerability is being used by ransomware groups.

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

Affected Version(s)

ADC 14.1 < 43.56

ADC 13.1 < 58.32

Gateway 14.1 < 43.56

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

News Articles

CVE-2025-5777 – Pre-Auth Memory Leak in Citrix NetScaler (CitrixBleed 2) - CYFIRMA

Published On : 2025-07-18 EXECUTIVE SUMMARY CVE‑2025‑5777 is a critical information disclosure vulnerability in Citrix NetScaler ADC and Gateway appliances, caused by unsafe memory handling in the...

6 days ago

Updates on Actively Exploited Information Disclosure Vulnerability “Citrix Bleed 2” in Citrix NetScaler ADC and Gateway I Arctic Wolf

In late June 2025, Arctic Wolf issued a security bulletin addressing a critical out-of-bounds read vulnerability in Citrix NetScaler ADC and Gateway that Citrix disclosed, tracked as CVE-2025-5777.

1 week ago

Citrix Bleed 2 exploited weeks before PoCs as Citrix denied attacks

A critical Citrix NetScaler vulnerability, tracked as CVE-2025-5777 and dubbed

2 weeks ago

References

EPSS Score

20% chance of being exploited in the next 30 days.

CVSS V4

Score:
9.3
Severity:
CRITICAL
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🦅

    CISA Reported

  • 🥇

    Vulnerability reached the number 1 worldwide trending spot

  • 📈

    Vulnerability started trending

  • 🟡

    Public PoC available

  • 💰

    Used in Ransomware

  • 👾

    Exploit known to exist

  • 📰

    First article discovered by GBHackers News

  • Vulnerability published

  • Vulnerability Reserved

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CVE-2025-5777 : Memory Overread Vulnerability in NetScaler Management Interface by Citrix