Cyber Resilience

CVE-2025-7776

Memory Safety in Citrix Netscaler Application Delivery Controller 12.1 – 12.1-55.330

Published
26 August 2025
Modified
17 June 2026
Patch / advisory
CVSS Score v4 8.8
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/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
EPSS Score 0.069 93th percentile
Risk Priority 52 floored blend · peak EPSS

Summary

CVE-2025-7776 is a high-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Citrix Netscaler Application Delivery Controller. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Process Injection (T1055); ranked in the top 7% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-8 (Security and Privacy Engineering Principles) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2025-7776 is a memory overflow vulnerability (CWE-119) affecting NetScaler ADC and NetScaler Gateway. The issue arises specifically when NetScaler is configured as a Gateway, including VPN virtual server, ICA Proxy, CVPN, or RDP Proxy configurations with a PCoIP Profile bound to it. This flaw can lead to unpredictable or erroneous behavior as well as Denial of Service conditions. It has a CVSS v3.1 base score of 9.8, reflecting its critical severity.

Remote attackers require no privileges or user interaction to exploit this vulnerability over the network with low complexity. Successful exploitation can result in high impacts to confidentiality, integrity, and availability, enabling attackers to cause denial of service or potentially execute arbitrary code due to the memory overflow.

For mitigation details, refer to the Citrix advisory at https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX694938.

EU & UK References

Vulnerability Data

Memory overflow vulnerability leading to unpredictable or erroneous behavior and Denial of Service in NetScaler ADC and NetScaler Gateway when NetScaler is configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) with PCoIP Profile bounded to it

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1055 Process Injection Stealth
Adversaries may inject code into processes in order to evade process-based defenses as well as possibly elevate privileges.
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-7775Same product: Citrix Netscaler Application Delivery Controller
CVE-2025-6543Same product: Citrix Netscaler Application Delivery Controller
CVE-2023-4966Same product: Citrix Netscaler Application Delivery Controller
CVE-2023-4967Same product: Citrix Netscaler Application Delivery Controller
CVE-2026-8655Same product: Citrix Netscaler Application Delivery Controller
CVE-2023-6549Same product: Citrix Netscaler Application Delivery Controller
CVE-2026-8452Same product: Citrix Netscaler Application Delivery Controller
CVE-2024-8534Same product: Citrix Netscaler Application Delivery Controller
CVE-2026-3055Same product: Citrix Netscaler Application Delivery Controller
CVE-2026-10817Same product: Citrix Netscaler Application Delivery Controller

Affected Assets

citrix
netscaler application delivery controller
12.1 — 12.1-55.330 · 12.1 — 12.1-55.330 · 13.1 — 13.1-37.241
citrix
netscaler gateway
13.1 — 13.1-59.22 · 14.1 — 14.1-47.48

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V17.3.2

Mitigating Controls (NIST 800-53 r5) AI

Secure engineering principles require memory-safe design and coding that structurally avoids buffer-boundary violations.

Input validation directly enforces bounds checking that stops out-of-bounds reads/writes from being introduced or reached.

Memory protection restricts exploitation impact of buffer overflows without eliminating the underlying coding flaw.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices (bounds checking, safe APIs, reviews) directly prevent this class of flaw.

ID.RA-01 partial match
prevents

Vulnerability scanning and code analysis directly surface buffer-boundary flaws.

ID.RA-08 partial match
prevents

Receiving and triaging vulnerability disclosures commonly includes buffer-related reports.

PR.AT-02 partial match
prevents

Developer training on secure coding reduces introduction of memory-buffer errors.

PR.PS-02 partial match
prevents

Patching replaces vulnerable code containing buffer-boundary defects.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing in development catches out-of-bounds accesses before release, covering most instances of the weakness.

prevents

Secure development lifecycle mandates memory-safety practices that directly prevent buffer-boundary violations.

prevents

Application security requirements can specify memory-safety rules, but do not prescribe implementation details.

prevents

Secure architecture and engineering principles include memory-safe design patterns that mitigate buffer overflows.

prevents

Secure coding standards explicitly forbid unsafe buffer operations, directly eliminating CWE-119.

References