{"basis":"claimed","id":"CVE-2023-2868","name":"Barracuda Networks ESG Appliance Improper Input Validation Vulnerability","vendorProject":"Barracuda Networks","product":"Email Security Gateway (ESG) Appliance","publishedAt":"2023-05-24","cvss":{"score":9.4,"severity":"CRITICAL","version":"3.1"},"exploited":{"kevAdded":"2023-05-26","dueDate":"2023-06-16","ransomware":false},"epss":{"score":0.86841,"percentile":0.99744,"date":"2026-11-02"},"coverage":{"cloudflare":{"status":"no_history","firstOn":null,"daysToRule":null},"aws":{"status":"none","firstOn":null,"daysToRule":null},"azure":{"status":"none","firstOn":null,"daysToRule":null},"google":{"status":"no_history","firstOn":null,"daysToRule":null},"fastly":{"status":"no_history","firstOn":null,"daysToRule":null},"f5":{"status":"none","firstOn":null,"daysToRule":null},"akamai":{"status":"no_source","firstOn":null,"daysToRule":null},"crs":{"status":"none","firstOn":null,"daysToRule":null}},"title":"Remote Code injection in Barracuda Email Security Gateway","description":"A remote command injection vulnerability exists in the Barracuda Email Security Gateway (appliance form factor only) product effecting versions 5.1.3.001-9.2.0.006. The vulnerability arises out of a failure to comprehensively sanitize the processing of .tar file (tape archives). The vulnerability stems from incomplete input validation of a user-supplied .tar file as it pertains to the names of the files contained within the archive. As a consequence, a remote attacker can specifically format these file names in a particular manner that will result in remotely executing a system command through Perl's qx operator with the privileges of the Email Security Gateway product. This issue was fixed as part of BNSF-36456 patch. This patch was automatically applied to all customer appliances.","cwes":["CWE-20"],"vendors":[{"vendor":"cloudflare","status":"no_history","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"aws","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"azure","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"google","status":"no_history","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"fastly","status":"no_history","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"f5","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"akamai","status":"no_source","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"crs","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]}],"updatedAt":"2026-11-04T04:17:38.969Z","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L","ssvc":{"exploitation":"active","automatable":"yes","technicalImpact":"total"},"kevAction":"Apply updates per vendor instructions.","kevNotes":"https://status.barracuda.com/incidents/34kx82j5n4q9;  https://nvd.nist.gov/vuln/detail/CVE-2023-2868","references":[{"url":"https://www.barracuda.com/company/legal/esg-vulnerability","name":null,"tags":[]},{"url":"https://status.barracuda.com/incidents/34kx82j5n4q9","name":null,"tags":[]}],"affected":[{"vendor":"Barracuda","product":"Barracuda Email Security Gateway","affected":["5.1.3.001 to before 9.2.0.006"],"fixed":[]}],"briefing":{"status":{"id":"known_exploited","label":"Known exploited"},"why":"CISA lists CVE-2023-2868 as exploited in the wild since 2023-05-26. It is reachable over the network without credentials or any user interaction (CVSS 9.4). A Metasploit module exists, so exploitation needs no custom work. No edge WAF vendor names it in a changelog, so default managed rules may or may not catch it.","who":"Teams running Barracuda Barracuda Email Security Gateway (5.1.3.001 to before 9.2.0.006). Prioritise internet-facing instances.","what_to_do":[{"text":"Apply the vendor's fix; the advisory lists the affected and fixed versions.","href":"https://status.barracuda.com/incidents/34kx82j5n4q9","linkText":"status.barracuda.com"},{"text":"CISA's required action: Apply updates per vendor instructions. US federal agencies must act by 2023-06-16."},{"text":"Review exposed instances for signs of compromise: it was exploited before many systems were patched, and a later patch does not undo access already gained."},{"text":"Do not rely on WAF defaults: no edge vendor names this CVE. Restrict access to the vulnerable component or add a custom rule until it is patched.","href":"#edge","linkText":"Edge coverage"},{"text":"Check which WAF sits in front of your site and whether it covers this CVE.","href":"#check","linkText":"Check your domain"}],"evidence":[{"heading":"CVE record","text":"CVSS 3.1 9.4 (critical). Weakness: CWE-20.","links":[{"label":"CVE-2023-2868","href":"https://www.cve.org/CVERecord?id=CVE-2023-2868"},{"label":"NVD","href":"https://nvd.nist.gov/vuln/detail/CVE-2023-2868"}]},{"heading":"Vendor advisory","text":"Fixes and mitigations the CVE record links to. Check affected builds against the vendor, including backports.","links":[{"label":"status.barracuda.com","href":"https://status.barracuda.com/incidents/34kx82j5n4q9"}]},{"heading":"Exploit evidence","text":"Metasploit has a module.","links":[{"label":"Metasploit: Barracuda ESG TAR Filename Command Injection","href":"https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/linux/smtp/barracuda_esg_tarfile_rce.rb"}]},{"heading":"Seen exploited","text":"Claimed in 5 Telegram posts (unverified).","links":[]},{"heading":"CISA KEV","text":"Added 2023-05-26, federal due date 2023-06-16 (catalog 2026.11.03, checked 2026-11-04).","links":[{"label":"CISA KEV catalog","href":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2023-2868"}]},{"heading":"EPSS","text":"86.8% probability of exploitation activity in the next 30 days, higher than 99% of CVEs (2026-11-02).","links":[{"label":"FIRST EPSS","href":"https://api.first.org/data/v1/epss?cve=CVE-2023-2868"}]},{"heading":"WAF vendor statements","text":"No edge vendor changelog names it.","links":[]}],"agent_prompt":"Assess whether the infrastructure available to you is affected by CVE-2023-2868 (Barracuda Networks ESG Appliance Improper Input Validation Vulnerability). Perform a read-only assessment within your authorized access. Do not send exploit traffic, scan third-party systems, change configuration or restart services.\n\n1. Verify the CVE record at https://www.cve.org/CVERecord?id=CVE-2023-2868 and the vendor advisory. Establish affected and fixed versions, including vendor backports. The record lists: Barracuda Barracuda Email Security Gateway: affected 5.1.3.001 to before 9.2.0.006. Cite sources and retrieval dates; flag anything you cannot verify.\n2. Inventory deployments of Barracuda Networks Email Security Gateway (ESG) Appliance: asset, environment, owner where known, installed version or build, and how you confirmed it (package metadata, a version endpoint, image tags). An image tag alone does not prove the running version.\n3. Identify which deployments are reachable from the internet or untrusted networks, and through which paths (direct origin, load balancer, CDN or WAF).\n4. Assess compensating controls separately from patch status. Current edge WAF coverage for this CVE: no edge WAF vendor names it. Live data: https://cve.vigilbase.com/api/v1/cves/CVE-2023-2868. Check whether the rule is enabled and in block mode on each path, and whether any path bypasses the WAF. A WAF rule is not a patch.\n5. It is known exploited (CISA KEV): review logs on exposed instances for signs of exploitation before and after patching.\n\nReturn a short summary and a table: asset | version/build | assessment (affected, fixed, not applicable, unknown) | exposure | compensating control | evidence | next action. List what you could not assess and the access needed to resolve it. Do not infer absence of compromise from patch status or a lack of alerts.\n\nRemediation guidance: Apply the vendor's fix; the advisory lists the affected and fixed versions. CISA's required action: Apply updates per vendor instructions. US federal agencies must act by 2023-06-16.\nMore: https://cve.vigilbase.com/cve/CVE-2023-2868"},"measured":[],"sightings":{"honeypot":null,"catalog":null,"reports":[],"telegram":{"posts":5,"last":"2026-09-09"},"days":{"honeypot":[],"reports":[],"telegram":["2026-08-24","2026-09-04","2026-09-09"]}},"social":{"total":0,"first_seen":null,"daily":[{"day":"2026-10-22","posts":0},{"day":"2026-10-23","posts":0},{"day":"2026-10-24","posts":0},{"day":"2026-10-25","posts":0},{"day":"2026-10-26","posts":0},{"day":"2026-10-27","posts":0},{"day":"2026-10-28","posts":0},{"day":"2026-10-29","posts":0},{"day":"2026-10-30","posts":0},{"day":"2026-10-31","posts":0},{"day":"2026-11-01","posts":0},{"day":"2026-11-02","posts":0},{"day":"2026-11-03","posts":0},{"day":"2026-11-04","posts":0}],"top_posts":[],"exploit_repositories":[]}}