Status: KEV | Advisory ID: CVE-2021-23758
| CVE | CVE-2021-23758 |
| CVSS | CVSS 8.1 (High). |
| Affected products | Ajax.NET Professional Ajax.NET Professional, ajaxpro.2_project ajaxpro.2, and michaelschwarz ajax.net_professional |
| Exploitation status | Listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, indicating confirmed active exploitation. |
| Classified as | CWE-502 (Deserialization of Untrusted Data) |
| KEV listing | Added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2026-08-26. |
| Exploitation prediction (EPSS) | 84% probability of exploitation in the next 30 days (100% percentile) -- FIRST.org's EPSS model. |
| Federal remediation deadline | 2026-09-09 (CISA KEV, Binding Operational Directive). |
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.
| Source | Reference |
|---|---|
| NVD | https://nvd.nist.gov/vuln/detail/CVE-2021-23758 |