{"id":"CVE-2009-0557","published":"2009-06-10T18:30:00Z","modified":"2026-06-16T23:05:18Z","title":"Microsoft Office Object Record Corruption Vulnerability","vendor":"Microsoft","product":"Office","tier":"core","eol":null,"description":{"text":"Excel in Microsoft Office 2000 SP3, Office XP SP3, Office 2003 SP3, and Office 2004 and 2008 for Mac; Excel in 2007 Microsoft Office System SP1 and SP2; Open XML File Format Converter for Mac; Microsoft Office Excel Viewer 2003 SP3; Microsoft Office Excel Viewer; and Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP1 and SP2 allow remote attackers to execute arbitrary code via a crafted Excel file with a malformed record object, aka \"Object Record Corruption Vulnerability.\"","provenance":"source","from":"NVD"},"summary":{"text":"Microsoft Office's Excel component, across multiple Office and Excel Viewer versions and the Open XML converter and compatibility pack, mishandles malformed object records in Excel files, which is classified as improper control of code generation (code injection). An attacker can execute arbitrary code by getting a user to open a crafted Excel file, requiring user interaction and no authentication.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-23T07:13:13Z"},"cvss":{"score":7.8,"severity":"HIGH","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","provenance":"source","from":"NVD"},"epss":{"score":0.52845,"percentile":0.98968,"date":"2026-10-28","provenance":"source"},"kev":{"dateAdded":"2022-06-08","dueDate":"2022-06-22","ransomware":false,"requiredAction":"Apply updates per vendor instructions.","notes":"https://nvd.nist.gov/vuln/detail/CVE-2009-0557","provenance":"source"},"vulncheckKev":{"dateAdded":"2022-06-08","exploitedFirstSeen":"2022-06-08","ransomware":false,"evidence":[{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2022-06-08"}],"evidenceTotal":1,"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-94","name":"Improper Control of Generation of Code"}],"references":[{"url":"http://osvdb.org/54953","tags":["Broken Link"]},{"url":"http://www.securityfocus.com/bid/35241","tags":["Broken Link","Third Party Advisory","VDB Entry"]},{"url":"http://www.securitytracker.com/id?1022351","tags":["Broken Link","Third Party Advisory","VDB Entry"]},{"url":"http://www.us-cert.gov/cas/techalerts/TA09-160A.html","tags":["Broken Link","Third Party Advisory","US Government Resource"]},{"url":"http://www.vupen.com/english/advisories/2009/1540","tags":["Broken Link"]},{"url":"https://docs.microsoft.com/en-us/security-updates/securitybulletins/2009/ms09-021","tags":["Patch","Vendor Advisory"]},{"url":"https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A5564","tags":["Broken Link"]},{"url":"http://osvdb.org/54953","tags":["Broken Link"]},{"url":"http://www.securityfocus.com/bid/35241","tags":["Broken Link","Third Party Advisory","VDB Entry"]},{"url":"http://www.securitytracker.com/id?1022351","tags":["Broken Link","Third Party Advisory","VDB Entry"]},{"url":"http://www.us-cert.gov/cas/techalerts/TA09-160A.html","tags":["Broken Link","Third Party Advisory","US Government Resource"]},{"url":"http://www.vupen.com/english/advisories/2009/1540","tags":["Broken Link"]},{"url":"https://docs.microsoft.com/en-us/security-updates/securitybulletins/2009/ms09-021","tags":["Patch","Vendor Advisory"]},{"url":"https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A5564","tags":["Broken Link"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2009-0557","tags":["US Government Resource"]}],"techniques":[{"id":"T1204.002","name":"Malicious File","tactics":["execution"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: victim opens crafted Excel file","mappingType":"exploitation_technique","evidence":[{"from":"description","quote":"allow remote attackers to execute arbitrary code via a crafted Excel file","start":366,"end":439}],"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: arbitrary code execution from malformed record","mappingType":"primary_impact","evidence":[{"from":"description","quote":"allow remote attackers to execute arbitrary code via a crafted Excel file","start":366,"end":439}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"}],"reports":[],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2009-0561","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2009-0561","exploited":true,"exploitedSince":"2022-06-08","provenance":"source"},"exploits":[],"exploitSources":null,"exploitRefs":[],"flow":[{"stage":"exploitation","techniques":["T1204.002"],"provenance":"ai"},{"stage":"primary","techniques":["T1059"],"provenance":"ai"}],"timeline":[{"date":"2009-06-10","kind":"published","label":"Published (NVD)","url":"https://nvd.nist.gov/vuln/detail/CVE-2009-0557","provenance":"source"},{"date":"2022-06-08","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":"2022-06-08","kind":"kev","label":"Added to CISA KEV","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","provenance":"source"},{"date":"2022-06-08","kind":"euvd-exploited","label":"ENISA EUVD: exploited","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2009-0561","provenance":"source"}],"speed":{"daysToPublicExploit":null,"firstExploitFrom":null,"daysToKev":4746},"priority":{"score":63.3,"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 1604 days ago"},{"name":"Known ransomware use","points":0.0,"detail":"not known"},{"name":"EPSS percentile","points":19.79,"detail":"percentile 0.9897"},{"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":5.46,"detail":"base score 7.8"},{"name":"End-of-life product","points":0.0,"detail":"supported or unknown"}]},"lineage":{"familyId":"fam-class-microsoft-office-cwe-94"}}