{"id":"CVE-2019-18935","published":"2019-12-11T13:15:11Z","modified":"2026-06-17T02:25:36Z","title":"Progress Telerik UI for ASP.NET AJAX Deserialization of Untrusted Data Vulnerability","vendor":"Progress","product":"Telerik UI for ASP.NET AJAX","tier":"core","eol":null,"description":{"text":"Progress Telerik UI for ASP.NET AJAX through 2019.3.1023 contains a .NET deserialization vulnerability in the RadAsyncUpload function. This is exploitable when the encryption keys are known due to the presence of CVE-2017-11317 or CVE-2017-11357, or other means. Exploitation can result in remote code execution. (As of 2020.1.114, a default setting prevents the exploit. In 2019.3.1023, but not earlier versions, a non-default setting can prevent exploitation.)","provenance":"source","from":"NVD"},"summary":null,"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":0.99737,"percentile":0.99954,"date":"2026-10-30","provenance":"source"},"kev":{"dateAdded":"2021-11-03","dueDate":"2022-05-03","ransomware":true,"requiredAction":"Apply updates per vendor instructions.","notes":"https://nvd.nist.gov/vuln/detail/CVE-2019-18935","provenance":"source"},"vulncheckKev":{"dateAdded":"2020-05-07","exploitedFirstSeen":"2020-05-07","ransomware":true,"evidence":[{"url":"https://redcanary.com/blog/blue-mockingbird-cryptominer/","date":"2020-05-07"},{"url":"https://lifars.com/knowledge-center/xmrig-based-coinminer-bluemockingbird-group/","date":"2020-06-01"},{"url":"https://www.telerik.com/blogs/blue-mockingbird-vulnerability-telerik-guidance","date":"2020-06-19"},{"url":"https://blog.talosintelligence.com/2020/09/CTIR-quarterly-trends-Q4-2020.html","date":"2020-09-01"},{"url":"https://www.hhs.gov/sites/default/files/netwalker.pdf","date":"2020-09-24"},{"url":"https://cisa.gov/news-events/cybersecurity-advisories/aa20-275a","date":"2020-10-20"},{"url":"https://media.defense.gov/2020/Oct/20/2002519884/-1/-1/0/CSA_CHINESE_EXPLOIT_VULNERABILITIES_UOO179811.PDF","date":"2020-10-20"},{"url":"https://us-cert.cisa.gov/ncas/alerts/aa20-275a","date":"2020-10-20"},{"url":"https://cdn.pathfactory.com/assets/10753/contents/298161/03f15d14-01bb-462b-a8d4-d8c6149f5604.pdf","date":"2021-03-05"},{"url":"https://www.hhs.gov/sites/default/files/revil-update-tlpwhite.pdf","date":"2021-08-19"}],"evidenceTotal":492,"provenance":"source"},"exploited":true,"otx":{"pulseCount":50,"pulses":[{"name":"Actively_Exploited_Kev 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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-502","name":"Deserialization of Untrusted Data"}],"references":[{"url":"http://packetstormsecurity.com/files/155720/Telerik-UI-Remote-Code-Execution.html","tags":["Third Party Advisory","VDB Entry"]},{"url":"http://packetstormsecurity.com/files/159653/Telerik-UI-ASP.NET-AJAX-RadAsyncUpload-Deserialization.html","tags":["Exploit","Third Party Advisory","VDB Entry"]},{"url":"https://codewhitesec.blogspot.com/2019/02/telerik-revisited.html","tags":["Not Applicable"]},{"url":"https://github.com/bao7uo/RAU_crypto","tags":["Exploit","Third Party Advisory"]},{"url":"https://github.com/noperator/CVE-2019-18935","tags":["Exploit","Third Party Advisory"]},{"url":"https://know.bishopfox.com/research/cve-2019-18935-remote-code-execution-in-telerik-ui","tags":["Exploit","Third Party Advisory"]},{"url":"https://www.bleepingcomputer.com/news/security/us-federal-agency-hacked-using-old-telerik-bug-to-steal-data/","tags":["Press/Media Coverage"]},{"url":"https://www.telerik.com/support/kb/aspnet-ajax/details/allows-javascriptserializer-deserialization","tags":["Patch","Vendor Advisory"]},{"url":"https://www.telerik.com/support/whats-new/aspnet-ajax/release-history/ui-for-asp-net-ajax-r1-2020-%28version-2020-1-114%29","tags":["Release Notes"]},{"url":"https://www.telerik.com/support/whats-new/release-history","tags":["Release Notes","Vendor Advisory"]},{"url":"http://packetstormsecurity.com/files/155720/Telerik-UI-Remote-Code-Execution.html","tags":["Third Party Advisory","VDB Entry"]},{"url":"http://packetstormsecurity.com/files/159653/Telerik-UI-ASP.NET-AJAX-RadAsyncUpload-Deserialization.html","tags":["Exploit","Third Party Advisory","VDB Entry"]},{"url":"https://codewhitesec.blogspot.com/2019/02/telerik-revisited.html","tags":["Not Applicable"]},{"url":"https://github.com/bao7uo/RAU_crypto","tags":["Exploit","Third Party Advisory"]},{"url":"https://github.com/noperator/CVE-2019-18935","tags":["Exploit","Third Party Advisory"]},{"url":"https://know.bishopfox.com/research/cve-2019-18935-remote-code-execution-in-telerik-ui","tags":["Exploit","Third Party Advisory"]},{"url":"https://www.bleepingcomputer.com/news/security/us-federal-agency-hacked-using-old-telerik-bug-to-steal-data/","tags":["Press/Media Coverage"]},{"url":"https://www.telerik.com/support/kb/aspnet-ajax/details/allows-javascriptserializer-deserialization","tags":["Patch","Vendor 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This vulnerability leads to the application being vulnerable to RCE attacks that may lead to a full system compromise. ","confidence":"high"},{"id":"T1041","name":"Exfiltration Over C2 Channel","tactics":["exfiltration"],"provenance":"source","basis":"ctid-kev","bases":["ctid-kev"],"basisDetail":"CTID Mappings Explorer KEV 07/28/2025 (ATT&CK 16.1); capability: Deserialization of Untrusted Data","mappingType":"primary_impact","evidence":[],"comment":"CVE 2019-18935 is a Insecure Deserialization vulnerability with the Telerik UI, which does not properly sanitize serialized data inputs from the user. This vulnerability leads to the application being vulnerable to RCE attacks that may lead to a full system compromise. ","confidence":"high"},{"id":"T1496","name":"Resource Hijacking","tactics":["impact"],"provenance":"source","basis":"ctid-kev","bases":["ctid-kev"],"basisDetail":"CTID Mappings Explorer KEV 07/28/2025 (ATT&CK 16.1); capability: Deserialization of Untrusted Data","mappingType":"primary_impact","evidence":[],"comment":"CVE 2019-18935 is a Insecure Deserialization vulnerability with the Telerik UI, which does not properly sanitize serialized data inputs from the user. This vulnerability leads to the application being vulnerable to RCE attacks that may lead to a full system compromise. ","confidence":"high"},{"id":"T1505.003","name":"Web Shell","tactics":["persistence"],"provenance":"source","basis":"ctid-kev","bases":["ctid-kev"],"basisDetail":"CTID Mappings Explorer KEV 07/28/2025 (ATT&CK 16.1); capability: Deserialization of Untrusted Data","mappingType":"primary_impact","evidence":[],"comment":"CVE 2019-18935 is a Insecure Deserialization vulnerability with the Telerik UI, which does not properly sanitize serialized data inputs from the user. This vulnerability leads to the application being vulnerable to RCE attacks that may lead to a full system compromise. ","confidence":"high"},{"id":"T1189","name":"Drive-by Compromise","tactics":["initial-access"],"provenance":"source","basis":"ctid-cve","bases":["ctid-cve"],"basisDetail":"CTID attack_to_cve (Phase 1)","mappingType":"uncategorized","evidence":[],"confidence":"low","confidenceNote":"server-side bug exploitable without user interaction; client-execution technique does not fit"},{"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":"server-side bug exploitable without user interaction; client-execution technique does not fit"}],"reports":[{"id":"SRC-c5682f0140a36049d2bb","title":"Blue Mockingbird activity mines Monero cryptocurrency","publisher":"redcanary.com","url":"https://redcanary.com/blog/threat-intelligence/blue-mockingbird-cryptominer/","date":null,"mentions":[{"quote":"This suite of user interface components accelerates the web development process, but some versions are susceptible to a deserialization vulnerability, CVE-2019-18935.","start":968,"end":1134}]}],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2019-8608","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2019-8608","exploited":true,"exploitedSince":"2021-11-03","provenance":"source"},"exploits":[{"id":47793,"url":"https://www.exploit-db.com/exploits/47793","title":"Telerik UI - Remote Code Execution via Insecure Deserialization","type":"webapps","platform":"aspx","date":"2019-12-18","verified":false,"provenance":"source"}],"exploitSources":{"exploitdb":{"count":1,"earliest":"2019-12-18"},"pocGithub":{"count":16,"skipped":1,"earliest":"2018-01-09","earliestUrl":"https://github.com/bao7uo/RAU_crypto","repos":[{"name":"noperator/CVE-2019-18935","url":"https://github.com/noperator/CVE-2019-18935","stars":373,"created":"2019-12-12"},{"name":"bao7uo/RAU_crypto","url":"https://github.com/bao7uo/RAU_crypto","stars":179,"created":"2018-01-09"},{"name":"murataydemir/CVE-2019-18935","url":"https://github.com/murataydemir/CVE-2019-18935","stars":16,"created":"2020-08-19"},{"name":"dust-life/CVE-2019-18935-memShell","url":"https://github.com/dust-life/CVE-2019-18935-memShell","stars":13,"created":"2023-12-25"},{"name":"ThanHuuTuan/Telerik_CVE-2019-18935","url":"https://github.com/ThanHuuTuan/Telerik_CVE-2019-18935","stars":12,"created":"2020-05-25"}]},"metasploit":[{"name":"Telerik UI ASP.NET AJAX RadAsyncUpload Deserialization","module":"exploit/windows/http/telerik_rau_deserialization","type":"exploit","disclosureDate":"2019-12-09","url":"https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/windows/http/telerik_rau_deserialization.rb"}],"first":{"date":"2018-01-09","source":"PoC-in-GitHub","url":"https://github.com/bao7uo/RAU_crypto"},"provenance":"source"},"exploitRefs":["http://packetstormsecurity.com/files/159653/Telerik-UI-ASP.NET-AJAX-RadAsyncUpload-Deserialization.html","https://github.com/bao7uo/RAU_crypto","https://github.com/noperator/CVE-2019-18935","https://know.bishopfox.com/research/cve-2019-18935-remote-code-execution-in-telerik-ui","http://packetstormsecurity.com/files/155720/Telerik-UI-Remote-Code-Execution.html"],"flow":[{"stage":"exploitation","techniques":["T1190"],"provenance":"source"},{"stage":"primary","techniques":["T1505.003","T1041","T1496"],"provenance":"source"},{"stage":"related","techniques":["T1189","T1203"],"provenance":"source","lowConfidence":true}],"timeline":[{"date":"2018-01-09","kind":"exploit-public","label":"First public exploit: PoC-in-GitHub; 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