#VU111237 Out-of-bounds read in Citrix Netscaler ADC and Citrix NetScaler Gateway - CVE-2025-5777

Vulnerability identifier: #VU111237

Vulnerability risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2025-5777

CWE-ID: CWE-125

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Citrix Netscaler ADC
Client/Desktop applications / Software for system administration
Citrix NetScaler Gateway
Server applications / Application servers

Vendor: Citrix

Description

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to a boundary condition. A remote attacker can send specially crafted data to the server, trigger an out-of-bounds read error and read contents of memory on the system.

Successful exploitation of the vulnerability requires that NetScaler is configured as Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Citrix Netscaler ADC: 12.0 - 14.1-43.50

Citrix NetScaler Gateway: 13.0-36.27 - 14.1-43.50

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External links
https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX693420

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.