{"schema":"threatline.record/2","record":{"id":"CVE-2021-23758","aliases":[],"summary":"Ajax.NET Professional Deserialization of Untrusted Data Vulnerability","details":"Ajax.NET Professional (AjaxPro) contains a deserialization of untrusted data vulnerability that could allow for remote code execution via arbitrary .NET classes. The impacted product(s) could be end-of-life (EoL) and/or end-of-service (EoS). Users are advised to discontinue use and/or transition to a supported version.","categories":["Unclassified"],"product":"Ajax.NET Professional","vendor":"Ajax.NET Professional","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2021-23758","source_modified_at":"2026-08-27T03:56:43.403Z","fetched_at":"2026-10-23T18:42:43.628194Z","product":"AjaxPro.2","vendor":"n/a","versions":[{"version":"0","status":"affected","lessThan":"unspecified","versionType":"custom"}],"defaultStatus":null}],"fixed_versions":[],"cvss":8.1,"severity":"High","kev":{"listed":true,"date_added":"2026-08-26","due_date":"2026-09-09","required_action":"Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.","ransomware_campaign_use":"Unknown"},"epss":{"probability":0.82578,"percentile":0.99666,"score_date":"2026-10-23"},"published_at":"2021-12-03T20:05:12.932Z","modified_at":"2026-08-27T03:56:43.403Z","provenance":[{"source":"CISA KEV","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23T17:00:09.9001Z"},{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2021-23758","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-08-27T03:56:43.403Z"},{"source":"Metasploit","url":"https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/windows/http/ajaxpro_deserialization_rce.rb","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2021-12-03"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2021-23758","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CISA KEV","CVE List","Metasploit","EPSS"],"references":[{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-23758","source":"CISA KEV"},{"source":"CVE List","url":"https://snyk.io/vuln/SNYK-DOTNET-AJAXPRO2-1925971","tags":["x_transferred"]},{"source":"CVE List","url":"https://github.com/michaelschwarz/Ajax.NET-Professional/commit/b0e63be5f0bb20dfce507cb8a1a9568f6e73de57","tags":["x_transferred"]},{"source":"CVE List","url":"https://blog.talosintelligence.com/uat-10147-chinese-speaking-adversary-integrates-agentic-ai-into-post-compromise-operations/","tags":["third-party-advisory"]},{"source":"CVE List","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-23758","tags":["government-resource"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"active","automatable":"no","technical_impact":"total","assessed_at":"2026-08-26T00:00:00+00:00"},"exploits":[{"source":"Metasploit","kind":"Exploit module","name":"AjaxPro Deserialization Remote Code Execution","url":"https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/windows/http/ajaxpro_deserialization_rce.rb","date":"2021-12-03","added":"2025-12-17","check":true}],"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":null,"confidence":"unknown","reviewed":false},"change_timestamp":"2026-08-27T03:56:43.403Z","content_hash":"04e25acdd5c0e41fa47dd6d56134ac070c343b7db9a1c25e143f6a39292d7454"}}