{"id":"CVE-2020-5135","published":"2020-10-12T11:15:12Z","modified":"2026-06-17T03:20:57Z","title":"SonicWall SonicOS Buffer Overflow Vulnerability","vendor":"SonicWall","product":"SonicOS","tier":"core","eol":null,"description":{"text":"A buffer overflow vulnerability in SonicOS allows a remote attacker to cause Denial of Service (DoS) and potentially execute arbitrary code by sending a malicious request to the firewall. This vulnerability affected SonicOS Gen 6 version 6.5.4.7, 6.5.1.12, 6.0.5.3, SonicOSv 6.5.4.v and Gen 7 version 7.0.0.0.","provenance":"source","from":"NVD"},"summary":{"text":"A buffer overflow in SonicWall's SonicOS firewall operating system lets an attacker cause denial of service and potentially execute arbitrary code. The attack requires only network access to the device and a malicious request, with no authentication, user interaction, or special configuration needed.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-29T08:32:07Z"},"cvss":{"score":9.8,"severity":"CRITICAL","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","provenance":"source","from":"NVD"},"epss":{"score":0.26869,"percentile":0.9803,"date":"2026-10-29","provenance":"source"},"kev":{"dateAdded":"2022-03-15","dueDate":"2022-04-05","ransomware":true,"requiredAction":"Apply updates per vendor instructions.","notes":"https://nvd.nist.gov/vuln/detail/CVE-2020-5135","provenance":"source"},"vulncheckKev":{"dateAdded":"2022-03-15","exploitedFirstSeen":"2022-03-15","ransomware":true,"evidence":[{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2022-03-15"},{"url":"https://www.paloaltonetworks.com/content/dam/pan/en_US/assets/pdf/reports/2022-unit42-ransomware-threat-report-final.pdf","date":"2022-03-24"},{"url":"https://cybersecurityworks.com/howdymanage/uploads/file/Spotlight%20Report%20-%20Index%20Update%20Q2%20-%20Q3%20-%20Final%20Version_compressed.pdf","date":"2022-05-18"},{"url":"https://static.tenable.com/marketing/whitepapers/Whitepaper-Ransomware_Ecosystem.pdf","date":"2022-06-22"},{"url":"https://www.ivanti.com/resources/v/doc/pr-survey-report/ransomware-quarterly-indexreport_q2-q3","date":"2022-10-21"},{"url":"https://cert-in.org.in/PDF/RANSOMWARE_Report_2022.pdf","date":"2023-04-22"},{"url":"https://go.recordedfuture.com/hubfs/reports/cta-2024-0208.pdf","date":"2024-02-08"}],"evidenceTotal":7,"provenance":"source"},"exploited":true,"otx":{"pulseCount":50,"pulses":[{"name":"Actively_Exploited_Kev | Oct 29, 2026","url":"https://otx.alienvault.com/pulse/6ae20c1db17e7057ae7d9ad1","created":"2026-10-28"},{"name":"Actively_Exploited_Kev | Oct 28, 2026","url":"https://otx.alienvault.com/pulse/6ae0ba7e0e2a97ff7b218819","created":"2026-10-27"},{"name":"Actively_Exploited_Kev | Oct 27, 2026","url":"https://otx.alienvault.com/pulse/6adf68b85c3e852f3c111d18","created":"2026-10-26"},{"name":"Actively_Exploited_Kev | Oct 24, 2026","url":"https://otx.alienvault.com/pulse/6adb740e397c3ad4799aa4cd","created":"2026-10-23"},{"name":"Actively_Exploited_Kev | Oct 23, 2026","url":"https://otx.alienvault.com/pulse/6ada236fcfba2dfa730ea482","created":"2026-10-22"},{"name":"Actively_Exploited_Kev | Oct 22, 2026","url":"https://otx.alienvault.com/pulse/6ad8d33a077cbb5cab524d80","created":"2026-10-21"},{"name":"Actively_Exploited_Kev | Oct 21, 2026","url":"https://otx.alienvault.com/pulse/6ad78130c4d1ac2be83a8b6d","created":"2026-10-20"},{"name":"Actively_Exploited_Kev | Oct 20, 2026","url":"https://otx.alienvault.com/pulse/6ad62f63c24a405a3423cc13","created":"2026-10-19"},{"name":"Actively_Exploited_Kev | Oct 19, 2026","url":"https://otx.alienvault.com/pulse/6ad4dda174e5797d0bd238b7","created":"2026-10-18"},{"name":"Actively_Exploited_Kev | Oct 18, 2026","url":"https://otx.alienvault.com/pulse/6ad38c22e1848f8189d1c121","created":"2026-10-17"}],"provenance":"machine"},"cwes":[{"id":"CWE-120","name":"Buffer Copy without Checking Size of Input"}],"references":[{"url":"https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2020-0010","tags":["Vendor Advisory"]},{"url":"https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2020-0010","tags":["Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-5135","tags":["US Government Resource"]}],"techniques":[{"id":"T1190","name":"Exploit Public-Facing Application","tactics":["initial-access"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: remote unauthenticated request to public-facing firewall","mappingType":"exploitation_technique","evidence":[{"from":"description","quote":"sending a malicious request to the firewall","start":143,"end":186}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"},{"id":"T1059","name":"Command and Scripting Interpreter","tactics":["execution"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: buffer overflow enables arbitrary code execution","mappingType":"primary_impact","evidence":[{"from":"description","quote":"potentially execute arbitrary code","start":105,"end":139}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"},{"id":"T1499.004","name":"Application or System Exploitation","tactics":["impact"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: overflow can crash the firewall service","mappingType":"primary_impact","evidence":[{"from":"description","quote":"cause Denial of Service (DoS)","start":71,"end":100}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"}],"reports":[],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2020-26382","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2020-26382","exploited":true,"exploitedSince":"2022-03-15","provenance":"source"},"exploits":[],"exploitSources":null,"exploitRefs":[],"flow":[{"stage":"exploitation","techniques":["T1190"],"provenance":"ai"},{"stage":"primary","techniques":["T1059","T1499.004"],"provenance":"ai"}],"timeline":[{"date":"2020-10-12","kind":"published","label":"Published (NVD)","url":"https://nvd.nist.gov/vuln/detail/CVE-2020-5135","provenance":"source"},{"date":"2022-03-15","kind":"exploited-reported","label":"Exploitation first reported (VulnCheck KEV evidence)","url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","provenance":"source"},{"date":"2022-03-15","kind":"kev","label":"Added to CISA KEV (known ransomware use)","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","provenance":"source"},{"date":"2022-03-15","kind":"euvd-exploited","label":"ENISA EUVD: exploited","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2020-26382","provenance":"source"}],"speed":{"daysToPublicExploit":null,"firstExploitFrom":null,"daysToKev":519},"priority":{"score":74.5,"factors":[{"name":"In a KEV catalog","points":35.0,"detail":"listed in CISA KEV and VulnCheck KEV"},{"name":"Recent KEV listing","points":0.0,"detail":"added 1689 days ago"},{"name":"Known ransomware use","points":10.0,"detail":"CISA KEV and VulnCheck KEV: Known"},{"name":"EPSS percentile","points":19.61,"detail":"percentile 0.9803"},{"name":"Named in threat reports","points":0.0,"detail":"0 reports"},{"name":"Public exploit code","points":0.0,"detail":"none found"},{"name":"Mentioned in OTX pulses","points":3.0,"detail":"50 pulses"},{"name":"CVSS severity","points":6.86,"detail":"base score 9.8"},{"name":"End-of-life product","points":0.0,"detail":"supported or unknown"}]}}