{"id":"CVE-2009-4171","url":"https://www.cyber-defence.io/tools/cve/CVE-2009-4171","generatedAt":"2026-10-27T17:38:24.713Z","title":"Messenger 9.0.0.2162, and possibly other 9.0 versions, allows remote attackers to cause a denial of service (NULL pointer dereference and application crash) by calling the RegisterMe method with a long argument.","description":"An ActiveX control in YahooBridgeLib.dll for Yahoo! Messenger 9.0.0.2162, and possibly other 9.0 versions, allows remote attackers to cause a denial of service (NULL pointer dereference and application crash) by calling the RegisterMe method with a long argument.","published":"2009-12-02T19:30:00.000Z","lastModified":"2026-06-16T23:13:11.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"2.0","score":4.3,"severity":"MEDIUM","vector":"AV:N/AC:M/Au:N/C:N/I:N/A:P"},"cwe":["CWE-119"],"affected":["yahoo/messenger"],"epss":{"score":0.05087,"percentile":0.92293,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":2,"verified":true,"firstPublished":"2009-11-12","source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[{"edbId":33350,"kind":"exploit","title":"Yahoo! Messenger 9 - 'YahooBridgeLib.dll' ActiveX Control Remote Denial of Service","url":"https://www.exploit-db.com/exploits/33350","sourceUrl":"https://gitlab.com/exploit-database/exploitdb/-/blob/main/exploits/windows/dos/33350.xml","file":"exploits/windows/dos/33350.xml","published":"2009-11-12","added":"2009-11-12","updated":"2014-05-14","author":"HACKATTACK","type":"dos","platform":"windows","port":null,"verified":true,"codes":["CVE-2009-4171","OSVDB-60629"],"tags":null,"aliases":null,"applicationUrl":null,"screenshotUrl":null,"referenceUrl":"https://www.securityfocus.com/bid/37007/info"},{"edbId":10092,"kind":"exploit","title":"Yahoo! Messenger 9.0.0.2162 - 'YahooBridgeLib.dll' ActiveX Control Remote Denial of Service","url":"https://www.exploit-db.com/exploits/10092","sourceUrl":"https://gitlab.com/exploit-database/exploitdb/-/blob/main/exploits/windows/dos/10092.txt","file":"exploits/windows/dos/10092.txt","published":"2009-11-12","added":"2009-11-11","updated":null,"author":"HACKATTACK","type":"dos","platform":"windows","port":null,"verified":true,"codes":["CVE-2009-4171","OSVDB-60629"],"tags":null,"aliases":null,"applicationUrl":null,"screenshotUrl":null,"referenceUrl":null}]},"verdict":{"level":"high","text":"2 public exploits are published in Exploit-DB (verified), so the technical barrier is gone even though the severity is medium and EPSS is 5.1%. Treat it as high on anything reachable from the internet."},"changes":[],"references":[{"url":"http://www.securityfocus.com/archive/1/507818/100/0/threaded","source":"cve@mitre.org"},{"url":"http://www.securityfocus.com/bid/37007","tags":["Exploit"],"source":"cve@mitre.org"},{"url":"https://exchange.xforce.ibmcloud.com/vulnerabilities/54263","source":"cve@mitre.org"},{"url":"http://www.securityfocus.com/archive/1/507818/100/0/threaded","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.securityfocus.com/bid/37007","tags":["Exploit"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://exchange.xforce.ibmcloud.com/vulnerabilities/54263","source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2009-4171","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}