CVE-2023-6549

HIGH CISA KEV

Published Jan 17, 2024 Modified Feb 26, 2026 CWE-119

Description

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

CVSS v3.1 Score

8.2

HIGH

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

CISA Known Exploited Vulnerability

This vulnerability is actively exploited in the wild.

Added: Jan 17, 2024 Remediation due: Feb 7, 2024

Weakness Type (CWE)

CWE-119 Buffer Overflow

Affected Products

Vendor	Product	Versions
citrix	netscaler_application_delivery_controller	12.1 — 12.1-55.302
citrix	netscaler_application_delivery_controller	12.1 — 12.1-55.302
citrix	netscaler_application_delivery_controller	13.0 — 13.0-92.21
citrix	netscaler_application_delivery_controller	13.1 — 13.1-37.176
citrix	netscaler_application_delivery_controller	13.1 — 13.1-51.15
citrix	netscaler_application_delivery_controller	14.1 — 14.1-12.35
citrix	netscaler_gateway	13.0 — 13.0-92.21
citrix	netscaler_gateway	13.1 — 13.1-51.15
citrix	netscaler_gateway	14.1 — 14.1-12.35

References

Advisories & Patches

https://support.citrix.com/article/CTX584986/netscaler-adc-and-netscaler-gateway-security-bulletin-for-cve20236548-and-cve20236549 https://support.citrix.com/article/CTX584986/netscaler-adc-and-netscaler-gateway-security-bulletin-for-cve20236548-and-cve20236549

Other References

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-6549

Frequently Asked Questions

What is CVE-2023-6549? +

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 It has a CVSS v3.1 base score of 8.2 (HIGH). This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog, indicating active exploitation in the wild.

How severe is CVE-2023-6549? +

CVE-2023-6549 has a CVSS v3.1 score of 8.2 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2023-6549? +

CVE-2023-6549 affects products from citrix, specifically: netscaler_application_delivery_controller, netscaler_gateway. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-6549? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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