{"answers":{"affected":"It affects 2 products.","exploited":"Yes. Attackers have exploited CVE-2023-4966 in the wild since at least 18 Oct 2023, including in ransomware campaigns.","fix":"No fix has been published for CVE-2023-4966 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 8 Nov 2023.","what":"CVE-2023-4966 (Citrix Bleed) is a critical vulnerability in Citrix NetScaler ADC, published on 10 Oct 2023. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2023-4966 (Citrix Bleed) and fix it if it is affected.\n\nWhat it is: CVE-2023-4966 (Citrix Bleed) is a critical vulnerability in Citrix NetScaler ADC, published on 10 Oct 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: Yes. Attackers have exploited CVE-2023-4966 in the wild since at least 18 Oct 2023, including in ransomware campaigns.\n\nAffected product: Citrix NetScaler ADC. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2023-4966/ (Markdown: https://insights.sbomify.com/CVE-2023-4966/index.md)","id":"CVE-2023-4966","markdown":"https://insights.sbomify.com/CVE-2023-4966/index.md","name":"CVE-2023-4966 (Citrix Bleed)","record":{"aliases":["GHSA-2g42-2pwg-93cj"],"analysis":{"component_type":"network_device","fix_type":"patch","impacts":["data_read","account_takeover"],"network_reachable":"yes","non_default_config":true,"product_category":"Citrix NetScaler ADC","requires_auth":"none","summary":"Unauthenticated attackers can disclose sensitive session data from Citrix NetScaler ADC and Gateway when configured as a Gateway or AAA virtual server.","user_interaction":"not_required","vuln_class":"information_disclosure"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Citrix","cpe":[{"product":"netscaler_application_delivery_controller","vendor":"citrix"},{"product":"netscaler_gateway","vendor":"citrix"}],"cvss":{"score":9.4,"severity":"critical","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L","version":"3.1"},"cwes":[{"id":"CWE-119","name":"Improper Restriction of Operations within the Bounds of a Memory Buffer"}],"description":"Sensitive information disclosure in NetScaler ADC and NetScaler Gateway when configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) or AAA  virtual server.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":"2023-10-24","github_poc":14,"max_poc_stars":78,"metasploit":1,"nuclei":1,"refs":[{"date":"2023-10-24T17:19:32Z","kind":"github_poc","ref":"https://github.com/Chocapikk/CVE-2023-4966","stars":78,"title":"Sensitive information disclosure in NetScaler ADC and NetScaler Gateway when configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) or AAA virtual server. "},{"date":"2023-10-25T04:15:17Z","kind":"github_poc","ref":"https://github.com/dinosn/citrix_cve-2023-4966","stars":10,"title":"Citrix CVE-2023-4966 from assetnote modified for parallel and file handling"},{"date":"2023-10-29T15:31:37Z","kind":"github_poc","ref":"https://github.com/RevoltSecurities/CVE-2023-4966","stars":10,"title":"An Exploitation script developed to exploit the CVE-2023-4966 bleed citrix information disclosure vulnerability"},{"date":"2023-10-25T12:37:56Z","kind":"github_poc","ref":"https://github.com/mlynchcogent/CVE-2023-4966-POC","stars":8,"title":"Proof Of Concept for te NetScaler Vuln"},{"date":"2023-10-28T11:44:42Z","kind":"github_poc","ref":"https://github.com/certat/citrix-logchecker","stars":5,"title":"Parse citrix netscaler logs to check for signs of CVE-2023-4966 exploitation"},{"date":"2023-12-16T21:55:04Z","kind":"github_poc","ref":"https://github.com/morganwdavis/overread","stars":2,"title":"Simulates CVE-2023-4966 Citrix Bleed overread bug"},{"date":"2023-10-25T21:34:43Z","kind":"github_poc","ref":"https://github.com/IceBreakerCode/CVE-2023-4966","stars":1,"title":null},{"date":"2023-10-25","kind":"metasploit","ref":"auxiliary/scanner/http/citrix_bleed_cve_2023_4966","stars":null,"title":"Citrix ADC (NetScaler) Bleed Scanner"}],"tier":"exploited"},"has_fix":null,"headline":"Citrix NetScaler ADC and NetScaler Gateway Buffer Overflow","id":"CVE-2023-4966","indexable":true,"kev":{"dateAdded":"2023-10-18","dueDate":"2023-11-08","knownRansomwareCampaignUse":"Known","product":"NetScaler ADC and NetScaler Gateway","requiredAction":"Apply mitigations and kill all active and persistent sessions per vendor instructions [https://www.netscaler.com/blog/news/cve-2023-4966-critical-security-update-now-available-for-netscaler-adc-and-netscaler-gateway/] OR discontinue use of the product if mitigations are unavailable.","vendorProject":"Citrix","vulnerabilityName":"Citrix NetScaler ADC and NetScaler Gateway Buffer Overflow Vulnerability"},"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"information_disclosure","year":"2023"},"n_packages":0,"n_references":2,"next":{"headline":"Denial of service","id":"CVE-2023-4967"},"packages":[],"prev":{"headline":"phpipam Header redirect","id":"CVE-2023-4965"},"products":["NetScaler ADC","NetScaler Gateway"],"published":"2023-10-10","related":[{"cvss_score":9.8,"headline":"Citrix NetScaler ADC and NetScaler Gateway Code Injection","id":"CVE-2023-3519","kev_date_added":"2023-07-19","published":"2023-07-19"},{"cvss_score":9.5,"headline":"Citrix NetScaler Improper Input Validation","id":"CVE-2026-88771","kev_date_added":"2026-09-27","published":"2026-09-27"},{"cvss_score":9.5,"headline":"Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer","id":"CVE-2026-88772","kev_date_added":"2026-09-27","published":"2026-09-27"},{"cvss_score":9.3,"headline":"Citrix NetScaler Authentication Bypass Using an Alternate Path or Channel","id":"CVE-2026-19490","kev_date_added":"2026-09-09","published":"2026-08-19"},{"cvss_score":9.3,"headline":"Citrix NetScaler Out-of-Bounds Read","id":"CVE-2026-3055","kev_date_added":"2026-03-30","published":"2026-03-23"},{"cvss_score":9.3,"headline":"Citrix NetScaler ADC and Gateway Out-of-Bounds Read","id":"CVE-2025-5777","kev_date_added":"2025-07-10","published":"2025-06-17"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"open","licence":"CC0 1.0","name":"CISA KEV"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"},{"class":"attribution","licence":"BSD-3-Clause","name":"Metasploit"},{"class":"open","licence":"CC0","name":"PoC-in-GitHub"}],"ssvc":{"automatable":"yes","exploitation":"active","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-07-31","vendors":["Citrix"]},"summary":"Unauthenticated attackers can disclose sensitive session data from Citrix NetScaler ADC and Gateway when configured as a Gateway or AAA virtual server.","url":"https://insights.sbomify.com/CVE-2023-4966/"}