What is the GHSA ID for CVE-2023-4966?

GitHub tracks CVE-2023-4966 as GHSA-2g42-2pwg-93cj.

What is the CVSS score of CVE-2023-4966?

CVE-2023-4966 has a CVSS 3.1 base score of 9.4 (Critical), vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L.

Which versions are affected by CVE-2023-4966?

Citrix NetScaler ADC (Vendor product): >= 14.1, = 13.1, = 13.0, = 13.1-FIPS, = 12.1-FIPS, = 12.1-NDcPP, = 14.1, = 13.1, = 13.0, < 92.19.

How do I fix CVE-2023-4966?

No fixed version has been published yet. Check the advisory and references for mitigations, and watch the vendor for a release.

Is CVE-2023-4966 exploited in the wild?

CISA lists it as a known exploited vulnerability (added 18 Oct 2023). CISA's SSVC assessment rates exploitation as "active". EPSS estimates a 99.99% chance of exploitation in the next 30 days, higher than 99.9% of CVEs.

CVE-2023-4966GHSA-2g42-2pwg-93cj

Unauthenticated sensitive information disclosure

Q: How do I fix CVE-2023-4966?

No fixed version has been published yet. Check the advisory and references for mitigations, and watch the vendor for a release.

Q: Is CVE-2023-4966 exploited in the wild?

CISA lists it as a known exploited vulnerability (added 18 Oct 2023). CISA's SSVC assessment rates exploitation as "active". EPSS estimates a 99.99% chance of exploitation in the next 30 days, higher than 99.9% of CVEs.

CVE-2023-4966 (GitHub advisory GHSA-2g42-2pwg-93cj) is a critical-severity vulnerability with a CVSS 3.1 base score of 9.4, classed as Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119), in Citrix NetScaler ADC and Citrix NetScaler Gateway. No fixed version has been published yet. CISA lists it as a known exploited vulnerability (added 18 Oct 2023).

Critical9.4Known exploitedNo fix yetUnreviewed advisory

Published 10 Oct 2023Updated 31 Jul 2026

9.4CriticalCVSS 3.1

CVE ID: CVE-2023-4966
GHSA ID: GHSA-2g42-2pwg-93cj
EPSS: 99.99%higher than 99.9% of CVEs
Weakness (CWE): CWE-119Improper Restriction of Operations within the Bounds of a Memory Buffer
KEV status: Known exploitedAdded 18 Oct 2023
Published: 10 Oct 2023
Updated: 31 Jul 2026
Ecosystem: Vendor product
Assigned by (CNA): Citrix

Summary

Source: GitHub Advisory Database

Sensitive information disclosure in NetScaler ADC and NetScaler Gateway when configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) or AAA ?virtual?server.

Technical details

Source: GitHub Advisory Database

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L

Critical9.4Base score from GitHub Advisory Database

Attack Vector AV: Network
Attack Complexity AC: Low
Privileges Required PR: None
User Interaction UI: None
Scope S: Unchanged
Confidentiality C: High
Integrity I: High
Availability A: Low

CISA SSVC decision points

Exploitation: active; Exploited in the wild
Automatable: yes; Attackers can automate this at scale
Technical impact: total; Full control of the affected system

CISA Coordinator assessment (SSVC 2.0.3) via CVE.org.

CISA required action

Apply mitigations and kill all active and persistent sessions per vendor instructions [https://www.netscaler.com/blog/news/cve-2023-4966-critical-security-update-now-available-for-netscaler-adc-and-netscaler-gateway/] OR discontinue use of the product if mitigations are unavailable.

Federal agencies must remediate by 8 Nov 2023. Used in ransomware campaigns.

Affected packages

Source: CVE.org

Citrix NetScaler ADC
Vendor product
No PURL published
Affected versions
>= 14.1, < 8.50
>= 13.1, < 49.15
>= 13.0, < 92.19
>= 13.1-FIPS, < 37.164
>= 12.1-FIPS, < 55.300
>= 12.1-NDcPP, < 55.300
Fixed in
No fix yet
Citrix NetScaler Gateway
Vendor product
No PURL published
Affected versions
>= 14.1, < 8.50
>= 13.1, < 49.15
>= 13.0, < 92.19
Fixed in
No fix yet

Package	Affected versions	Fixed in
Citrix NetScaler ADC Vendor product No PURL published	>= 14.1, < 8.50 >= 13.1, < 49.15 >= 13.0, < 92.19 >= 13.1-FIPS, < 37.164 >= 12.1-FIPS, < 55.300 >= 12.1-NDcPP, < 55.300	No fix yet
Citrix NetScaler Gateway Vendor product No PURL published	>= 14.1, < 8.50 >= 13.1, < 49.15 >= 13.0, < 92.19	No fix yet

Fix

Source: CVE.org

No fixed version has been published

Every version in the affected ranges above is vulnerable. Look for mitigations in the advisory and references, and watch the vendor for a release.

Vulnerability intelligence

References

Advisories 2

Questions about CVE-2023-4966

What is the GHSA ID for CVE-2023-4966?: GitHub tracks CVE-2023-4966 as GHSA-2g42-2pwg-93cj.
What is the CVSS score of CVE-2023-4966?: CVE-2023-4966 has a CVSS 3.1 base score of 9.4 (Critical), vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L.
Which versions are affected by CVE-2023-4966?: Citrix NetScaler ADC (Vendor product): >= 14.1, < 8.50; >= 13.1, < 49.15; >= 13.0, < 92.19; >= 13.1-FIPS, < 37.164; >= 12.1-FIPS, < 55.300; >= 12.1-NDcPP, < 55.300. Citrix NetScaler Gateway (Vendor product): >= 14.1, < 8.50; >= 13.1, < 49.15; >= 13.0, < 92.19.
How do I fix CVE-2023-4966?: No fixed version has been published yet. Check the advisory and references for mitigations, and watch the vendor for a release.
Is CVE-2023-4966 exploited in the wild?: CISA lists it as a known exploited vulnerability (added 18 Oct 2023). CISA's SSVC assessment rates exploitation as "active". EPSS estimates a 99.99% chance of exploitation in the next 30 days, higher than 99.9% of CVEs.

Data sources

Upstream records

OSV (GitHub advisory)No record
GitHub Advisory DatabaseLoadedRaw JSON
OSV (CVE record)No record
CVE.orgLoaded
CISA KEV catalogLoaded

Fetched 2 days ago (12 Oct 2026, 03:38 UTC). Records refresh automatically after 24 hours.

Where each part of this page came from

Title and description: GitHub Advisory Database
Severity score: GitHub Advisory Database
Weakness (CWE): GitHub Advisory Database
Affected packages: CVE.org
Fix: CVE.org
References: Computed by CVEminer
SSVC: CVE.org
KEV status: CISA KEV catalog
EPSS: GitHub Advisory Database

OSV and GitHub Advisory Database content is licensed CC BY 4.0. Values marked as computed or derived were calculated by CVEminer from the upstream data.