Exploited Unauthenticated RCE Vulnerability CVE-2023-6548 in Citrix NetScaler ADC and NetScaler Gateway

New intelligence shows that exploitation of this RCE vulnerability does not require authentication

https://digital.nhs.uk/cyber-alerts/2024/cc-4525

The NHS England National Cyber Security Operations Centre (CSOC) is aware of intelligence provided by CrowdStrike that contrary to Citrix’s initial disclosure, the vulnerability known as CVE-2023-6548 does not require user privileges for exploitation. NHS England National CSOC now assesses CVE-2023-6548 as a critical vulnerability that can allow a remote, unauthenticated attacker to execute remote code on a vulnerable NetScaler Gateway or NetScaler ADC device.

CVE-2023-6548 has two different CVSSv3 scores attributed to it. The NIST National Vulnerability Database (NVD) has classified it as having a score of 8.8, while Citrix rates the vulnerability at 5.5. The weakness is Improper Control of Generation of Code ('Code Injection') in NetScaler ADC and NetScaler Gateway and could allow a remote, unauthenticated attacker with access to the management interface to execute arbitrary code.