# CVE-2023-4967 — Cloud Software Group NetScaler ADC

> As of 2025-02-27, CVE-2023-4967 is a HIGH-severity vulnerability in Cloud Software Group NetScaler ADC, CVSS v3.1 8.2, EPSS 0.8% (55.5th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2023-4967, most recently “Proofpoint AI Era Ransomware Report: 37% of Paying Victims Face Repeat Extortion Demands”.

**Last updated:** 2025-02-27

## What is CVE-2023-4967?

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

The record classifies CVE-2023-4967 under weakness class [CWE-119](https://cwe.mitre.org/data/definitions/119.html). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on availability. 2 affected-product entries are recorded, across 1 vendor, listed below. The identifier was first published 1052 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 8.2 — HIGH (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H`)
- **EPSS (FIRST):** 0.8% probability of exploitation in the next 30 days, higher than 55.5% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 8.3/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2023-10-27, last modified 2025-02-27

## Is CVE-2023-4967 being exploited?

Weaponised exploit code for CVE-2023-4967 is publicly available. 1 public proof-of-concept repository is tracked for this identifier.

- [trickest/cve](https://github.com/trickest/cve/blob/main/2023/CVE-2023-4967.md) (trickest)

## Affected products and versions

- **Cloud Software Group**: NetScaler ADC, NetScaler Gateway

## How to fix CVE-2023-4967

Vendor advisory: [https://support.citrix.com/article/CTX579459/](https://support.citrix.com/article/CTX579459/). Apply the vendor fix referenced above to every affected product listed in this record, then confirm the running version against the vendor advisory.

## Threat activity tracking CVE-2023-4967

1 tracked threat in the Threadlinqs corpus references CVE-2023-4967, either in the campaign’s CVE list or as an indicator on the campaign record.

- [Proofpoint AI Era Ransomware Report: 37% of Paying Victims Face Repeat Extortion Demands](https://intel.threadlinqs.com/threat/TL-2026-1710) — MEDIUM · 2026-07-22

## Sources

Enriched from CVE.org, NVD, FIRST EPSS, GitHub Security Advisories, public proof-of-concept repositories. Last verified by Threadlinqs on 2026-07-27. This product uses the NVD API but is not endorsed or certified by the NVD.

**Other references**

- [support.citrix.com](https://support.citrix.com/article/CTX579459/)

Canonical: https://intel.threadlinqs.com/cve/CVE-2023-4967
Full detection coverage and IOCs for threats exploiting CVE-2023-4967 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp