{"id":"CVE-2016-0034","published":"2016-01-13T05:59:22Z","modified":"2026-08-14T05:16:53Z","title":"Microsoft Silverlight Runtime Remote Code Execution Vulnerability","vendor":"Microsoft","product":"Silverlight","tier":"core","eol":{"product":"Microsoft Silverlight","since":"2021-10-12","note":"No security updates; remove it."},"description":{"text":"Microsoft Silverlight 5 before 5.1.41212.0 mishandles negative offsets during decoding, which allows remote attackers to execute arbitrary code or cause a denial of service (object-header corruption) via a crafted web site, aka \"Silverlight Runtime Remote Code Execution Vulnerability.\"","provenance":"source","from":"NVD"},"summary":{"text":"Microsoft Silverlight 5 before 5.1.41212.0 mishandles negative offsets during decoding, a flaw in its runtime's input validation. A remote attacker can execute arbitrary code or cause a denial of service through object-header corruption by luring a user to a crafted web site, requiring no authentication but user interaction.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-23T06:55:55Z"},"cvss":{"score":8.8,"severity":"HIGH","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","provenance":"source","from":"NVD"},"epss":{"score":0.69397,"percentile":0.99357,"date":"2026-10-28","provenance":"source"},"kev":{"dateAdded":"2022-05-25","dueDate":"2022-06-15","ransomware":true,"requiredAction":"The impacted products are end-of-life and should be disconnected if still in use.","notes":"https://nvd.nist.gov/vuln/detail/CVE-2016-0034","provenance":"source"},"vulncheckKev":{"dateAdded":"2015-11-25","exploitedFirstSeen":"2015-11-25","ransomware":true,"evidence":[{"url":"https://docs.google.com/spreadsheets/d/1lkNJ0uQwbeC1ZTRrxdtuPLCIl7mlUreoKfSIgajnSyY/edit","date":"2015-11-25"},{"url":"https://api.msrc.microsoft.com/cvrf/v3.0/cvrf/2016-Jan","date":"2016-01-12"},{"url":"https://securelist.com/the-mysterious-case-of-cve-2016-0034-the-hunt-for-a-microsoft-silverlight-0-day/73255/","date":"2016-01-13"},{"url":"https://us-cert.cisa.gov/ncas/alerts/TA17-164A","date":"2017-06-13"},{"url":"https://cisa.gov/news-events/alerts/2017/06/13/hidden-cobra-north-koreas-ddos-botnet-infrastructure","date":"2017-08-23"},{"url":"https://dl.acm.org/doi/pdf/10.1145/3465481.3465758","date":"2021-08-17"},{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2022-05-25"}],"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-20","name":"Improper Input Validation"}],"references":[{"url":"http://www.securitytracker.com/id/1034655","tags":["Broken Link","Third Party Advisory","VDB Entry"]},{"url":"https://docs.microsoft.com/en-us/security-updates/securitybulletins/2016/ms16-006","tags":["Patch","Vendor Advisory"]},{"url":"http://www.securitytracker.com/id/1034655","tags":["Broken Link","Third Party Advisory","VDB Entry"]},{"url":"https://docs.microsoft.com/en-us/security-updates/securitybulletins/2016/ms16-006","tags":["Patch","Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2016-0034","tags":["US Government Resource"]}],"techniques":[{"id":"T1189","name":"Drive-by Compromise","tactics":["initial-access"],"provenance":"source","basis":"ctid-cve","bases":["ctid-cve","ai-mapping"],"basisDetail":"CTID attack_to_cve (Phase 1); claude-haiku-5-5: Victim visits attacker-crafted website triggering decoding","mappingType":"uncategorized","evidence":[{"from":"description","quote":"via a crafted web site","start":200,"end":222}],"confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"},{"id":"T1203","name":"Exploitation for Client Execution","tactics":["execution"],"provenance":"source","basis":"ctid-cve","bases":["ctid-cve"],"basisDetail":"CTID attack_to_cve (Phase 1)","mappingType":"uncategorized","evidence":[],"confidence":"low","confidenceNote":"CTID attack_to_cve Phase 1 \"Uncategorized\" mapping (not staged by impact)"},{"id":"T1499.004","name":"Application or System Exploitation","tactics":["impact"],"provenance":"source","basis":"ctid-cve","bases":["ctid-cve","ai-mapping"],"basisDetail":"CTID attack_to_cve (Phase 1); claude-haiku-5-5: Crash via object-header corruption causes denial of service","mappingType":"uncategorized","evidence":[{"from":"description","quote":"cause a denial of service (object-header corruption)","start":147,"end":199}],"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: Arbitrary code execution from decoding flaw","mappingType":"primary_impact","evidence":[{"from":"description","quote":"allows remote attackers to execute arbitrary code","start":94,"end":143}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"}],"reports":[{"id":"SRC-3d89b3537203eabaf47a","title":"RATANKBA: Delving into Large-scale Watering Holes","publisher":"trendmicro.com","url":"https://www.trendmicro.com/en_us/research/17/b/ratankba-watering-holes-against-enterprises.html","date":"2017-02-27","mentions":[{"quote":"detected as SWF_EXPLOYT.YYRQ)\nA Silverlight (.xap) file containing several files: an App Manifest (AppManifest.xaml), and DLLs Shell_siver.dll (TROJ_CVE20130074.B), and System.Xml.Linq.dll, which when repacked form a runtime remote code execution exploit for Silverlight (CVE-2016-0034, patched last January 12,","start":5537,"end":5848}]},{"id":"SRC-93c55e10ab45afc37c85","title":"Microsoft Security","publisher":"download.microsoft.com","url":"https://download.microsoft.com/download/E/B/0/EB0F50CC-989C-4B66-B7F6-68CD3DC90DE3/Microsoft_Security_Intelligence_Report_Volume_21_English.pdf","date":null,"mentions":[{"quote":"vulnerabilities, CVE-2015-1671 and CVE-2016-0034.","start":118236,"end":118285},{"quote":"CVE-2016-0034 Silverlight “GetChars()” memory","start":119222,"end":119267},{"quote":" CVE-2016-0034 - Silverlight “GetChars()” memory","start":124356,"end":124405},{"quote":"16 Costin Raiu and Anton Ivanov, “The mysterious case of CVE-2016-0034: the hunt for a Microsoft Silverlight 0-","start":125709,"end":125820},{"quote":"day,” Securelist, January 13, 2016, https://securelist.com/blog/research/73255/the-mysterious-case-of-cve-\r\n2016-0034-the-hunt-for-a-microsoft-silverlight-0-day/.","start":125822,"end":125984}]},{"id":"SRC-37b543b4cde4966b286b","title":"MONSOON – ANALYSIS OF AN APT CAMPAIGN","publisher":"forcepoint.com","url":"https://www.forcepoint.com/sites/default/files/resources/files/forcepoint-security-labs-monsoon-analysis-report.pdf","date":null,"mentions":[{"quote":"could have been intended as an exploitation of something like CVE-2016-0034 which is known to have","start":32765,"end":32863}]}],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2016-0072","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2016-0072","exploited":true,"exploitedSince":"2022-05-25","provenance":"source"},"exploits":[],"exploitSources":null,"exploitRefs":[],"flow":[{"stage":"primary","techniques":["T1059"],"provenance":"ai"},{"stage":"related","techniques":["T1189","T1499.004"],"provenance":"source"},{"stage":"related","techniques":["T1203"],"provenance":"source","lowConfidence":true}],"timeline":[{"date":"2015-11-25","kind":"exploited-reported","label":"Exploitation first reported (VulnCheck KEV evidence)","url":"https://docs.google.com/spreadsheets/d/1lkNJ0uQwbeC1ZTRrxdtuPLCIl7mlUreoKfSIgajnSyY/edit","provenance":"source"},{"date":"2016-01-13","kind":"published","label":"Published (NVD)","url":"https://nvd.nist.gov/vuln/detail/CVE-2016-0034","provenance":"source"},{"date":"2017-02-27","kind":"report","label":"Named in trendmicro.com: RATANKBA: Delving into Large-scale Watering Holes","url":"https://www.trendmicro.com/en_us/research/17/b/ratankba-watering-holes-against-enterprises.html","provenance":"machine"},{"date":"2022-05-25","kind":"kev","label":"Added to CISA KEV (known ransomware use)","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","provenance":"source"},{"date":"2022-05-25","kind":"euvd-exploited","label":"ENISA EUVD: exploited","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2016-0072","provenance":"source"}],"speed":{"daysToPublicExploit":null,"firstExploitFrom":null,"daysToKev":2324},"priority":{"score":66.8,"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 3991 days ago"},{"name":"Known ransomware use","points":10.0,"detail":"CISA KEV and VulnCheck KEV: Known"},{"name":"EPSS percentile","points":19.87,"detail":"percentile 0.9936"},{"name":"Named in threat reports","points":7.74,"detail":"3 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":6.16,"detail":"base score 8.8"},{"name":"End-of-life product","points":-15.0,"detail":"No patches exist; remove or isolate it"}]}}