CVE-2023-6549: Citrix NetScaler ADC and NetScaler Gateway Buffer Overflow Vulnerability

CISA Known Exploited Vulnerability (KEV)

Description

Citrix NetScaler ADC and NetScaler Gateway contain a buffer overflow vulnerability that allows for a denial-of-service when configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) or AAA virtual server.

Required action (CISA)

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

Notes

https://support.citrix.com/article/CTX584986/netscaler-adc-and-netscaler-gateway-security-bulletin-for-cve20236548-and-cve20236549; https://nvd.nist.gov/vuln/detail/CVE-2023-6549

Weakness behind it

CISA records this vulnerability as an instance of CWE-119. From there the chain continues into CAPEC attack patterns and ATT&CK techniques, all inside this corpus.

References

• NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-6549
• KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog