Security Resilience

CVE-2023-4967

Memory Safety in Citrix Netscaler Application Delivery Controller 13.0 – 13.0-92.19

Published
27 October 2023
Modified
21 November 2024
Patch / advisory
CVSS Score v3.1 8.2
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
EPSS Score 0.011 65th percentile
Risk Priority 63 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2023-4967 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 8.2 (High).

Operationally, ranked in the top 35% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability Data

Denial of Service in NetScaler ADC and NetScaler Gateway when configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) or AAA Virtual Server

CWE(s)

Related Threats

Threat-Actor AttributionAI

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CVEs Like This One

CVE-2023-6549Same product: Citrix Netscaler Application Delivery Controller
CVE-2026-88772Same product: Citrix Netscaler Application Delivery Controller
CVE-2025-6543Same product: Citrix Netscaler Application Delivery Controller
CVE-2026-88777Same product: Citrix Netscaler Application Delivery Controller
CVE-2026-88776Same product: Citrix Netscaler Application Delivery Controller
CVE-2026-8655Same product: Citrix Netscaler Application Delivery Controller
CVE-2025-7775Same product: Citrix Netscaler Application Delivery Controller
CVE-2026-88779Same product: Citrix Netscaler Application Delivery Controller
CVE-2025-7776Same product: Citrix Netscaler Application Delivery Controller
CVE-2026-8452Same product: Citrix Netscaler Application Delivery Controller

Affected Assets

citrix
netscaler application delivery controller
13.0 — 13.0-92.19 · 13.1 — 13.1-49.15 · 14.1 — 14.1-8.50
citrix
netscaler gateway
13.0 — 13.0-92.19 · 13.1 — 13.1-49.15 · 14.1 — 14.1-8.50

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-119

Ongoing control assessments and code testing (static/dynamic analysis, fuzzing) surface memory buffer restriction failures, which are then remediated before release.

addresses: CWE-119

Managed runtimes used by platform-independent applications (e.g., JVM, CLR) enforce memory safety, preventing most buffer overflows that require direct memory manipulation.

addresses: CWE-119

Memory protections (e.g., W^X, ASLR) make exploitation of buffer-boundary violations far harder to turn into code execution.

addresses: CWE-119

Detects exploitation attempts that produce memory corruption, crashes, or anomalous behavior.

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.

blocks

A.8.25 mandates secure SDLC practices (secure coding guidelines, security requirements, testing including code scans and penetration tests, developer training) that reach buffer management and can stop many buffer overruns from reaching production, but leaves a bounded remainder (e.g. flaws in non-software components, incomplete enforcement of guidelines, or post-deployment changes)

blocks

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

blocks

A.8.27 mandates security-by-design principles (e.g. least privilege, fail securely, distrust external input, hardening) plus design reviews that can catch and stop buffer-boundary errors before they reach code, but this is only one minority slice of CWE-119's broad surface (language-specific flaws, unsafe library use, compiler/runtime mitigations, and post-deployment instances remain outside its direct scope).

prevents

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

finds

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

Hardening callouts derived

DISA STIG baselines are authored against specific weaknesses. Where this CVE cites a broad weakness class, the mapping is not asserted at that abstraction (owner ruling, 2026-09-25: grade only at Base and below), so no rule is shown here rather than a rule shown against the wrong grain.

  • No fine-grained STIG row for CWE-119, a class-level weakness. Rules are authored against its narrower children: CWE-823.

References