CVE-2021-23758: Ajax.NET Professional Deserialization of Untrusted Data Vulnerability
Summary: Ajax.NET Professional (AjaxPro) contains a deserialization of untrusted data vulnerability, tracked as CVE-2021-23758, that could allow remote code execution via arbitrary .NET classes. CISA notes the affected product could be end-of-life or end-of-service and advises users to discontinue use or transition to a supported version, with a remediation due date of 2026-09-09.
Key Takeaway: The fix CISA points to is not a patch but abandonment of the product, so any team still running AjaxPro has to find and replace it before the September 2026 deadline - and CISA lists ransomware campaign use of this CVE as unknown.
Read the original at CISA KEV Catalog ↗
- Topics
- Vulnerabilities & Patching
- Mentions
- Ajax.NET ProfessionalCVE-2021-23758
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