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.

CVSS v3 8.1 HIGH
CVSS v2.0 7.5 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

7.5^/10

CVSS v2.0 : HIGH

Vector : AV:N/AC:L/Au:N/C:P/I:P/A:P

Exploitability : 10.0 / Impact : 6.4

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
http://packetstormsecurity.com/files/175677/AjaxPro-Deserialization-Remote-Code-Execution.html	Exploit VDB Entry
https://github.com/michaelschwarz/Ajax.NET-Professional/commit/b0e63be5f0bb20dfce507cb8a1a9568f6e73de57	Patch Third Party Advisory
https://snyk.io/vuln/SNYK-DOTNET-AJAXPRO2-1925971	Third Party Advisory
http://packetstormsecurity.com/files/175677/AjaxPro-Deserialization-Remote-Code-Execution.html	Exploit VDB Entry
https://github.com/michaelschwarz/Ajax.NET-Professional/commit/b0e63be5f0bb20dfce507cb8a1a9568f6e73de57	Patch Third Party Advisory
https://snyk.io/vuln/SNYK-DOTNET-AJAXPRO2-1925971	Third Party Advisory
https://blog.talosintelligence.com/uat-10147-chinese-speaking-adversary-integrates-agentic-ai-into-post-compromise-operations/	Exploit Third Party Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-23758	US Government Resource

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:ajaxpro.2_project:ajaxpro.2::::::.net::*
	cpe:2.3:a:michaelschwarz:ajax.net_professional::::::.net::*

History

No history.

Information

Published : 2021-12-03 20:15

Updated : 2026-08-27 04:16

NVD link : CVE-2021-23758

Mitre link : CVE-2021-23758

CVE.ORG link : CVE-2021-23758

JSON object : View

Products Affected

ajaxpro.2_project

ajaxpro.2

michaelschwarz

ajax.net_professional

CWE

CWE-502

Deserialization of Untrusted Data

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{"url": "https://snyk.io/vuln/SNYK-DOTNET-AJAXPRO2-1925971", "tags": ["Third Party Advisory"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://blog.talosintelligence.com/uat-10147-chinese-speaking-adversary-integrates-agentic-ai-into-post-compromise-operations/", "tags": ["Exploit", "Third Party Advisory"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}, {"url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-23758", "tags": ["US Government Resource"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-502"}]}, {"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-502"}]}], "descriptions": [{"lang": "en", "value": "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."}, {"lang": "es", "value": "Todas las versiones del paquete ajaxpro.2 son vulnerables a una Deserializaci\u00f3n de Datos No Confiables debido a la posibilidad de deserializaci\u00f3n de clases .NET arbitrarias, que pueden ser abusadas para obtener la ejecuci\u00f3n de c\u00f3digo remota"}], "lastModified": "2026-08-27T04:16:38.863", "cisaActionDue": "2026-09-09", "cisaExploitAdd": "2026-08-26", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:ajaxpro.2_project:ajaxpro.2:*:*:*:*:*:.net:*:*", "vulnerable": true, "matchCriteriaId": "0C5825C3-B14F-47EB-9FD9-324A314A5177"}, {"criteria": "cpe:2.3:a:michaelschwarz:ajax.net_professional:*:*:*:*:*:.net:*:*", "vulnerable": true, "matchCriteriaId": "3F7FC210-4C84-424D-AE68-BC3DB95F88AA", "versionEndExcluding": "21.10.30.1"}], "operator": "OR"}]}], "sourceIdentifier": "report@snyk.io", "cisaRequiredAction": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA\u2019s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA\u2019s \u201cForensics Triage Requirements\u201d (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.", "cisaVulnerabilityName": "Ajax.NET Professional Deserialization of Untrusted Data Vulnerability"}