CVE-2021-23758
CVSS v3
9.8
CRITICAL
EPSS Score
87.8 %
exploit probability
CISA KEV
Yes
known exploited
Exploitation
—
SSVC status
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.
CISA Known Exploited Vulnerability
- Date Added
- 2026-08-26
- Patch Due Date
- 2026-09-09
- Ransomware Use
- Unknown
Technical details
- Published
- 2021-12-03
Frequently asked questions
What is CVE-2021-23758?
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.
Is CVE-2021-23758 actively exploited?
Yes. CVE-2021-23758 is on the CISA Known Exploited Vulnerabilities (KEV) catalog, meaning it has been confirmed as actively exploited in the wild. CISA requires federal agencies to patch by 2026-09-09.
What is the CVSS score for CVE-2021-23758?
CVE-2021-23758 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2021-23758 affecting your environment?
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