Deserialization of Untrusted Data

Answer in brief

CVE-2021-23758 records a Unknown severity vulnerability in Deserialization of Untrusted Data. The current sources do not mark it as known exploited. The current feed maps n/a/AjaxPro.2 (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Dec 3, 2021Updated Aug 26, 2026Source checked Aug 26, 2026First seen by HOL Aug 26, 2026Material review Aug 26, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps n/a/AjaxPro.2 (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
n/a/AjaxPro.2generic	>=0 <unspecified	unspecified

Recommended response

Check inventory. Check lockfiles and deployed manifests for n/a/AjaxPro.2.
Review the reported fix. Update n/a/AjaxPro.2 to unspecified if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Dec 3, 2021
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 26, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 26, 2026

Sources and claim methodology

Upstream source 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.

Quoted source text, attributed separately from HOL analysis.