Known Exploited Vulnerability
9.3
CRITICAL CVSS 4.0
CVE-2025-5777
Citrix NetScaler ADC and Gateway Out-of-Bounds Read Vulnerability - [Actively Exploited]
Description

Insufficient input validation leading to memory overread when the NetScaler is configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server

INFO

Published Date :

June 17, 2025, 1:15 p.m.

Last Modified :

Oct. 30, 2025, 8:10 p.m.

Remotely Exploit :

Yes !
CISA Notification
CISA KEV (Known Exploited Vulnerabilities)

For the benefit of the cybersecurity community and network defenders—and to help every organization better manage vulnerabilities and keep pace with threat activity—CISA maintains the authoritative source of vulnerabilities that have been exploited in the wild.

Description :

Citrix NetScaler ADC and Gateway contain an out-of-bounds read vulnerability due to insufficient input validation. This vulnerability can lead to memory overread when the NetScaler is configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server.

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.

Notes :

https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX693420 ; https://nvd.nist.gov/vuln/detail/CVE-2025-5777

Affected Products

The following products are affected by CVE-2025-5777 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Citrix netscaler_application_delivery_controller
2 Citrix netscaler_gateway
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
CVSS 4.0 CRITICAL [email protected]
Solution
Update NetScaler to patch memory overread vulnerability.
  • Apply the latest NetScaler updates from the vendor.
  • Ensure secure configurations for Gateway and AAA virtual servers.
Public PoC/Exploit Available at Github

CVE-2025-5777 has a 41 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2025-5777 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2025-5777 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

None

Python

Updated: 1 week, 3 days ago
0 stars 0 fork 0 watcher
Born at : Nov. 23, 2025, 9:34 p.m. This repo has been linked 2 different CVEs too.

placeholder for CitrixBleed 2.0 CVE-2025-5777

Updated: 2 weeks, 4 days ago
0 stars 0 fork 0 watcher
Born at : Nov. 16, 2025, 9:14 a.m. This repo has been linked 1 different CVEs too.

CVE-2025-20337

Updated: 2 weeks, 6 days ago
0 stars 0 fork 0 watcher
Born at : Nov. 13, 2025, 3:39 p.m. This repo has been linked 3 different CVEs too.

Exploit for CVE-2025-5777: Citrix NetScaler Memory Disclosure (CitrixBleed 2)

citrixbleed-2 citrixbleed2 exploit-development

Shell

Updated: 3 months, 1 week ago
1 stars 0 fork 0 watcher
Born at : Aug. 20, 2025, 10:51 a.m. This repo has been linked 1 different CVEs too.

None

Updated: 3 months, 2 weeks ago
0 stars 0 fork 0 watcher
Born at : Aug. 15, 2025, 9:07 a.m. This repo has been linked 310 different CVEs too.

None

Python

Updated: 3 months, 2 weeks ago
0 stars 0 fork 0 watcher
Born at : Aug. 14, 2025, 10:09 p.m. This repo has been linked 1 different CVEs too.

Update the old POC of CVE-2025-5777 Citrix NetScaler Memory leak

Python

Updated: 3 months, 3 weeks ago
0 stars 1 fork 1 watcher
Born at : Aug. 11, 2025, 3:47 p.m. This repo has been linked 1 different CVEs too.

None

Python

Updated: 3 months, 3 weeks ago
1 stars 1 fork 1 watcher
Born at : Aug. 7, 2025, 8:47 p.m. This repo has been linked 1 different CVEs too.

CitrixBleed 2 NetScaler honeypot logs

Updated: 4 months ago
0 stars 0 fork 0 watcher
Born at : July 30, 2025, 1:43 p.m. This repo has been linked 1 different CVEs too.

None

Python

Updated: 3 months, 2 weeks ago
0 stars 0 fork 0 watcher
Born at : July 24, 2025, 12:09 p.m. This repo has been linked 1 different CVEs too.

PoC for CVE-2025-5777 – Auth Bypass and RCE in Trend Micro Apex Central

authentication-bypass cve-2025-5777 exploit infosec kali-linux python rce redteam trendmicro

Python

Updated: 4 months, 1 week ago
2 stars 0 fork 0 watcher
Born at : July 23, 2025, 12:05 p.m. This repo has been linked 1 different CVEs too.

None

Updated: 3 months, 2 weeks ago
1 stars 0 fork 0 watcher
Born at : July 23, 2025, 11:54 a.m. This repo has been linked 88 different CVEs too.

CVE-2025-5777

Python

Updated: 4 months, 2 weeks ago
0 stars 0 fork 0 watcher
Born at : July 16, 2025, 3:12 p.m. This repo has been linked 2 different CVEs too.

An advanced, powerful, and easy-to-use tool designed to detect and exploit CVE-2025-5777 (CitrixBleed 2). This script not only identifies the vulnerability but also helps in demonstrating its impact by parsing human-readable information from the memory leak.

Python

Updated: 4 months, 2 weeks ago
0 stars 0 fork 0 watcher
Born at : July 15, 2025, 5:49 p.m. This repo has been linked 1 different CVEs too.

CVE-2025-5777 (CitrixBleed 2) - [Citrix NetScaler ADC] [Citrix Gateway]

Python

Updated: 4 months, 2 weeks ago
0 stars 0 fork 0 watcher
Born at : July 15, 2025, 5:02 a.m. This repo has been linked 1 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2025-5777 vulnerability anywhere in the article.

  • The Cyber Express
Stolen VPN Credentials Most Common Ransomware Attack Vector

Compromised VPN credentials are the most common initial access vector for ransomware attacks, according to a new report. Nearly half of ransomware attacks in the third quarter abused compromised VPN c ... Read more

Published Date: Nov 20, 2025 (1 week, 6 days ago)
  • BleepingComputer
Pennsylvania AG confirms data breach after INC Ransom attack

The office of Pennsylvania's attorney general has confirmed that the ransomware gang behind an August 2025 cyberattack stole files containing personal and medical information. This comes after Attorne ... Read more

Published Date: Nov 17, 2025 (2 weeks, 2 days ago)
  • The Cyber Express
Android Reports Major Drop in Memory Bugs as Rust Adoption Accelerates

Android has shared new insights into how the platform’s long-term shift toward Rust is reshaping both security and software development. The new data reflects a decisive move toward memory safety, and ... Read more

Published Date: Nov 14, 2025 (2 weeks, 6 days ago)
  • The Cyber Express
Akira Ransomware Group Poses ‘Imminent Threat’ to Critical Infrastructure: CISA

The Akira ransomware group poses an “imminent threat to critical infrastructure,” the U.S. Cybersecurity and Infrastructure Security Agency (CISA) warned today. CISA joined with the FBI, other U.S. ag ... Read more

Published Date: Nov 13, 2025 (2 weeks, 6 days ago)
  • The Cyber Express
Ransomware Attacks Soared 30% in October

Ransomware attacks soared 30% in October to the second-highest total on record, Cyble reported today. The 623 ransomware attacks recorded in October were second only to February 2025’s record attacks, ... Read more

Published Date: Nov 13, 2025 (2 weeks, 6 days ago)
  • security.nl
Citrix Bleed en Cisco ISE-kwetsbaarheid als zero-day uitgebuit in geavanceerde aanvalscampagne

De Citrix Bleed 2 kwetsbaarheid (CVE-2025-5777) en een zero-day lek in een ongedocumenteerde endpoint van Cisco Identity Services Engine (ISE) (CVE-2025-20337) zijn door aanvallers uitgebuit voordat d ... Read more

Published Date: Nov 13, 2025 (3 weeks ago)
  • The Cyber Express
Zero-Day Vulnerabilities in Cisco and Citrix Targeted by APT Group, Amazon Confirms

Amazon’s threat intelligence division has revealed a cyber-espionage campaign involving an advanced persistent threat (APT) group exploiting previously undisclosed zero-day vulnerabilities in systems ... Read more

Published Date: Nov 13, 2025 (3 weeks ago)
  • The Register
Attackers turned Citrix, Cisco 0-day exploits into custom-malware hellscape

An "advanced" attacker exploited CitrixBleed 2 and a max-severity Cisco Identity Services Engine (ISE) bug as zero-days to deploy custom malware, according to Amazon Chief Information Security Officer ... Read more

Published Date: Nov 12, 2025 (3 weeks ago)
  • CybersecurityNews
Hackers Actively Exploiting Cisco and Citrix 0-Days in the Wild to Deploy Webshell

An advanced hacking group is actively exploiting zero-day vulnerabilities in Cisco Identity Services Engine (ISE) and Citrix systems. These attacks, spotted in real-world operations, allow hackers to ... Read more

Published Date: Nov 12, 2025 (3 weeks ago)
  • The Hacker News
Amazon Uncovers Attacks Exploited Cisco ISE and Citrix NetScaler as Zero-Day Flaws

Nov 12, 2025Ravie LakshmananNetwork Security / Zero-Day Amazon's threat intelligence team on Wednesday disclosed that it observed an advanced threat actor exploiting two then-zero-day security flaws ... Read more

Published Date: Nov 12, 2025 (3 weeks ago)
  • BleepingComputer
Hackers exploited Citrix, Cisco ISE flaws in zero-day attacks

An advanced threat actor exploited the critical vulnerabilities “Citrix Bleed 2" (CVE-2025-5777) in NetScaler ADC and Gateway, and CVE-2025-20337 affecting Cisco Identity Service Engine (ISE) as zero- ... Read more

Published Date: Nov 12, 2025 (3 weeks ago)
  • Trend Micro
The Rise of Collaborative Tactics Among China-aligned Cyber Espionage Campaigns

Key takeaways “Premier Pass-as-a-Service” describes the emerging trend of advanced collaboration tactics between multiple China-aligned APT groups, notably Earth Estries and Earth Naga, that are makin ... Read more

Published Date: Oct 22, 2025 (1 month, 1 week ago)
  • BleepingComputer
Citrix fixes critical NetScaler RCE flaw exploited in zero-day attacks

Citrix fixed three NetScaler ADC and NetScaler Gateway flaws today, including a critical remote code execution flaw tracked as CVE-2025-7775 that was actively exploited in attacks as a zero-day vulner ... Read more

Published Date: Aug 26, 2025 (3 months, 1 week ago)
  • Help Net Security
NetScaler ADC/Gateway zero-day exploited by attackers (CVE-2025-7775)

Three new vulnerabilities affecting (Citrix) NetScaler application delivery controller (ADC) and Gateway devices have been made public, one of which (CVE-2025-7775) has been targeted in zero-day attac ... Read more

Published Date: Aug 26, 2025 (3 months, 1 week ago)
  • CybersecurityNews
Qilin Ransomware Leads The Attack Landscape With 70+ Claimed Victims in July

The ransomware threat landscape witnessed a concerning surge in July 2025, with the Qilin ransomware group maintaining its dominant position for the third time in four months. The group successfully c ... Read more

Published Date: Aug 14, 2025 (3 months, 2 weeks ago)
  • BleepingComputer
Pennsylvania attorney general's email, site down after cyberattack

The Office of the Pennsylvania Attorney General has announced that a recent cyberattack has taken down its systems, including landline phone lines and email accounts. As Attorney General Dave Sunday r ... Read more

Published Date: Aug 13, 2025 (3 months, 2 weeks ago)
  • security.nl
NCSC publiceert scripts voor controleren van Citrix-systemen

Het Nationaal Cyber Security Centrum (NCSC) heeft vandaag op GitHub twee scripts gepubliceerd waarmee organisaties zelf kunnen controleren of hun Citrix-systemen zijn gecompromitteerd. Afgelopen maand ... Read more

Published Date: Aug 13, 2025 (3 months, 2 weeks ago)
  • The Register
Major outage at Pennsylvania Attorney General's Office blamed on 'cyber incident'

The Pennsylvania's Office of Attorney General (OAG) is blaming a digital blackout of its services on a "cyber incident." The OAG posted a statement to Facebook yesterday, saying that its systems are c ... Read more

Published Date: Aug 12, 2025 (3 months, 3 weeks ago)
  • CybersecurityNews
17,000+ VMware ESXi Servers Vulnerable to Critical Integer-Overflow Vulnerability

More than 17,000 VMware ESXi installations worldwide are at risk from a severe integer-overflow vulnerability tracked as CVE-2025-41236 (CVSS 9.3), cybersecurity researchers warn. This critical vulner ... Read more

Published Date: Aug 12, 2025 (3 months, 3 weeks ago)
  • CybersecurityNews
Critical Zoom Clients for Windows Vulnerability Lets Attackers Escalate Privileges

Zoom has disclosed a critical vulnerability affecting multiple Windows-based clients, potentially allowing attackers to escalate privileges and compromise user systems. Designated as CVE-2025-49457 un ... Read more

Published Date: Aug 12, 2025 (3 months, 3 weeks ago)

The following table lists the changes that have been made to the CVE-2025-5777 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • Modified Analysis by [email protected]

    Oct. 30, 2025

    Action Type Old Value New Value
    Added Reference Type CISA-ADP: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-5777 Types: US Government Resource
    Changed Reference Type CVE: https://citrixbleed.com Types: Third Party Advisory CVE: https://citrixbleed.com Types: Broken Link, Third Party Advisory
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Oct. 21, 2025

    Action Type Old Value New Value
    Added Reference https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-5777
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Oct. 21, 2025

    Action Type Old Value New Value
    Removed Reference https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-5777
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Oct. 21, 2025

    Action Type Old Value New Value
    Added Reference https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-5777
  • Modified Analysis by [email protected]

    Aug. 14, 2025

    Action Type Old Value New Value
    Added Reference Type CVE: https://citrixbleed.com Types: Third Party Advisory
  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Aug. 13, 2025

    Action Type Old Value New Value
    Added Reference https://citrixbleed.com
  • Modified Analysis by [email protected]

    Jul. 14, 2025

    Action Type Old Value New Value
    Added Reference Type CVE: https://horizon3.ai/attack-research/attack-blogs/cve-2025-5777-citrixbleed-2-write-up-maybe/ Types: Third Party Advisory
    Added Reference Type CVE: https://labs.watchtowr.com/how-much-more-must-we-bleed-citrix-netscaler-memory-disclosure-citrixbleed-2-cve-2025-5777/ Types: Third Party Advisory
    Added Reference Type CISA-ADP: https://reliaquest.com/blog/threat-spotlight-citrix-bleed-2-vulnerability-in-netscaler-adc-gateway-devices/ Types: Third Party Advisory
    Added Reference Type CVE: https://www.bleepingcomputer.com/news/security/cisa-tags-citrix-bleed-2-as-exploited-gives-agencies-a-day-to-patch/ Types: Press/Media Coverage, Third Party Advisory
    Added Reference Type CVE: https://www.netscaler.com/blog/news/netscaler-critical-security-updates-for-cve-2025-6543-and-cve-2025-5777/ Types: Third Party Advisory
    Added Reference Type CVE: https://www.theregister.com/2025/07/10/cisa_citrixbleed_kev/ Types: Press/Media Coverage
  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Jul. 12, 2025

    Action Type Old Value New Value
    Added Reference https://horizon3.ai/attack-research/attack-blogs/cve-2025-5777-citrixbleed-2-write-up-maybe/
    Added Reference https://labs.watchtowr.com/how-much-more-must-we-bleed-citrix-netscaler-memory-disclosure-citrixbleed-2-cve-2025-5777/
    Added Reference https://www.bleepingcomputer.com/news/security/cisa-tags-citrix-bleed-2-as-exploited-gives-agencies-a-day-to-patch/
    Added Reference https://www.netscaler.com/blog/news/netscaler-critical-security-updates-for-cve-2025-6543-and-cve-2025-5777/
    Added Reference https://www.theregister.com/2025/07/10/cisa_citrixbleed_kev/
  • CVE CISA KEV Update by 9119a7d8-5eab-497f-8521-727c672e3725

    Jul. 11, 2025

    Action Type Old Value New Value
    Added Date Added 2025-07-10
    Added Due Date 2025-07-11
    Added 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.
    Added Vulnerability Name Citrix NetScaler ADC and Gateway Out-of-Bounds Read Vulnerability
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jul. 10, 2025

    Action Type Old Value New Value
    Added Reference https://reliaquest.com/blog/threat-spotlight-citrix-bleed-2-vulnerability-in-netscaler-adc-gateway-devices/
  • Initial Analysis by [email protected]

    Jul. 10, 2025

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
    Added CWE CWE-908
    Added CPE Configuration OR *cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:-:*:*:* versions from (including) 13.1 up to (excluding) 13.1-58.32 *cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:-:*:*:* versions from (including) 14.1 up to (excluding) 14.1-43.56 *cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:fips:*:*:* versions from (including) 12.1 up to (excluding) 12.1-55.328 *cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:fips:*:*:* versions from (including) 13.1 up to (excluding) 13.1-37.235 *cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:ndcpp:*:*:* versions from (including) 13.1 up to (excluding) 13.1-37.235 *cpe:2.3:a:citrix:netscaler_gateway:*:*:*:*:*:*:*:* versions from (including) 13.1 up to (excluding) 13.1-58.32 *cpe:2.3:a:citrix:netscaler_gateway:*:*:*:*:*:*:*:* versions from (including) 14.1 up to (excluding) 14.1-43.56
    Added Reference Type CISA-ADP: https://doublepulsar.com/citrixbleed-2-exploitation-started-mid-june-how-to-spot-it-f3106392aa71 Types: Third Party Advisory
    Added Reference Type Citrix Systems, Inc.: https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX693420 Types: Vendor Advisory
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jul. 09, 2025

    Action Type Old Value New Value
    Added CWE CWE-457
    Added Reference https://doublepulsar.com/citrixbleed-2-exploitation-started-mid-june-how-to-spot-it-f3106392aa71
  • CVE Modified by [email protected]

    Jun. 24, 2025

    Action Type Old Value New Value
    Changed Description Insufficient input validation leading to memory overread on the NetScaler Management Interface NetScaler ADC and NetScaler Gateway Insufficient input validation leading to memory overread when the NetScaler is configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server
  • New CVE Received by [email protected]

    Jun. 17, 2025

    Action Type Old Value New Value
    Added Description Insufficient input validation leading to memory overread on the NetScaler Management Interface NetScaler ADC and NetScaler Gateway
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-125
    Added Reference https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX693420
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 9.3
Attack Vector
Attack Complexity
Attack Requirements
Privileges Required
User Interaction
VS Confidentiality
VS Integrity
VS Availability
SS Confidentiality
SS Integrity
SS Availability
Base CVSS Score: 7.5
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact