CVE-2021-23758: Ajax.NET Professional Deserialization of Untrusted Data Vulnerability
Actively exploited. At least one CVE in this advisory is listed in the CISA Known Exploited Vulnerabilities catalog — exploitation has been observed in the wild. Treat remediation as urgent.
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.
CSIRTS triage
- What
- Deserialization of untrusted data vulnerability allowing remote code execution via arbitrary .NET classes.
- Who is affected
- Applications using Ajax.NET Professional (AjaxPro); product may be end-of-life or end-of-service.
- Urgency
- Critical; actively exploited and supports unauthenticated remote code execution.
- Action
- Discontinue use of Ajax.NET Professional or transition to a supported and patched version.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2021-23758
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Exploitation confirmedCVE-2021-23758Already exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 99.8% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2021-23758 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
- highexploitedCISA Adds Six Known Exploited Vulnerabilities to Catalogcisa
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