{"id":"CVE-2023-6549","url":"https://www.cyber-defence.io/tools/cve/CVE-2023-6549","generatedAt":"2026-10-31T10:22:23.384Z","title":"Citrix NetScaler ADC and NetScaler Gateway Buffer Overflow Vulnerability","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","published":"2024-01-17T21:15:12.000Z","lastModified":"2026-06-17T06:50:58.000Z","status":"Analyzed","sourceIdentifier":"secure@citrix.com","cvss":{"version":"3.1","score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-119"],"affected":["citrix/netscaler application delivery controller","citrix/netscaler gateway"],"epss":{"score":0.57633,"percentile":0.99082,"date":"2026-10-30","history":[]},"kev":{"listed":true,"dateAdded":"2024-01-17","dueDate":"2024-02-07","knownRansomwareCampaignUse":"Unknown","notes":"Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.\nhttps://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"},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"urgent","text":"Known to be exploited in the wild (CISA KEV, CISA remediation deadline 7 February 2024). Treat as an emergency change: patch or isolate now, then hunt for prior compromise."},"changes":[],"references":[{"url":"https://support.citrix.com/article/CTX584986/netscaler-adc-and-netscaler-gateway-security-bulletin-for-cve20236548-and-cve20236549","tags":["Vendor Advisory"],"source":"secure@citrix.com"},{"url":"https://support.citrix.com/article/CTX584986/netscaler-adc-and-netscaler-gateway-security-bulletin-for-cve20236548-and-cve20236549","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-6549","tags":["US Government Resource"],"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2023-6549","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}