CVE-2021-23758
AjaxPro.2
Published 3 Dec 2021 · updated 27 Aug 2026 · Analyzed
Exploited in the wild
CISA added this to its Known Exploited Vulnerabilities catalog on 26 Aug 2026, with a remediation deadline of 9 Sept 2026 for US federal agencies.
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.
Description
All versions of package ajaxpro.2 are vulnerable to Deserialization of Untrusted Data due to the possibility of deserialization of arbitrary .NET classes, which can be abused to gain remote code execution.
References
- packetstormsecurity.com/files/175677/AjaxPro-Deserialization-Remote-Code-Execution.html · Exploit, VDB Entry
- github.com/michaelschwarz/Ajax.NET-Professional/commit/b0e63be5f0bb20dfce507cb8a1a9568f6e73de57 · Patch, Third Party Advisory
- snyk.io/vuln/SNYK-DOTNET-AJAXPRO2-1925971 · Third Party Advisory
- blog.talosintelligence.com/uat-10147-chinese-speaking-adversary-integrates-agentic-ai-into-post-compromise-operations/ · Exploit, Third Party Advisory
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-23758 · US Government Resource