Citrix NetScaler ADC/NetScaler Gateway memory corruption

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.6	$0-$5k	0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Citrix NetScaler ADC and NetScaler Gateway. Affected is an unknown function of the component Gateway. Such manipulation leads to memory corruption. This vulnerability is uniquely identified as CVE-2023-6549. The attack can be launched remotely. Moreover, an exploit is present. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Citrix NetScaler ADC and NetScaler Gateway (Network Management Software) (affected version unknown). Affected by this issue is an unknown functionality of the component Gateway. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. Impacted is confidentiality, integrity, and availability. CVE summarizes:

Improper Restriction of Operations within the Bounds of a Memory Buffer in NetScaler ADC and NetScaler Gateway allows Unauthenticated Denial of Service and Out-Of-Bounds Memory Read

The weakness was disclosed 01/16/2024 as CTX584986. The advisory is shared for download at support.citrix.com. This vulnerability is handled as CVE-2023-6549. Technical details are unknown but an exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 02/26/2026).

It is declared as attacked. This issue was added on 01/17/2024 to the CISA Known Exploited Vulnerabilities Catalog with a due date of 02/07/2024:

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Zero-Day.cz (850). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Network Management Software

Vendor

Citrix

Name

License

commercial

Website

Vendor: https://www.citrix.com/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.7
VulDB Meta Temp Score: 7.6

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CNA Base Score: 8.2
CNA Vector (Citrix Systems, Inc.): 🔍

CVSSv2info

AV	AC	Au	C	I	A
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Attacked

EPSS Score: 🔍
EPSS Percentile: 🔍

KEV Added: 🔍
KEV Due: 🔍
KEV Remediation: 🔍
KEV Ransomware: 🔍
KEV Notice: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Zero-Day.cz: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

12/06/2023 🔍
01/16/2024 +41 days 🔍
01/16/2024 +0 days 🔍
02/26/2026 +772 days 🔍

Sourcesinfo

Vendor: citrix.com

Advisory: CTX584986
Status: Confirmed

CVE: CVE-2023-6549 (🔍)
GCVE (CVE): GCVE-0-2023-6549
GCVE (VulDB): GCVE-100-250832
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 01/16/2024 16:16
Updated: 02/26/2026 10:05
Changes: 01/16/2024 16:16 (38), 01/17/2024 07:45 (3), 02/06/2024 08:46 (2), 02/06/2024 08:48 (21), 04/30/2024 11:45 (23), 06/05/2024 09:17 (2), 06/11/2024 05:20 (1), 09/09/2024 22:30 (2), 02/26/2026 10:05 (1)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.