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
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 9.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 83%
- Percentil entre todas las CVEs puntuadas: 100
- Fecha de la puntuación: 5/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
CISA KEV — explotada activamente
- Añadida al catálogo: 26/8/2026
- Plazo de remediación: 9/9/2026
- Uso conocido en ransomware: Unknown
💥 Exploits públicos
Hay código de explotación o plantillas de detección públicos. No es lo mismo que explotación activa confirmada (KEV), pero aumenta el riesgo: parchee con prioridad.
- Módulo de Metasploit (exploit fiable y al alcance de cualquiera) · AjaxPro Deserialization Remote Code Execution
- Prueba de concepto en GitHub (no verificada) · Lista de pruebas de concepto en GitHub
⚠️ Las pruebas de concepto de GitHub no están verificadas: algunas son falsas o contienen malware. No las ejecute nunca fuera de un laboratorio aislado.
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1190Exploit Public-Facing Applicationinitial access85 % - Impacto principal
T1059Command and Scripting Interpreterexecution90 %
Aplicación expuesta en red sin autenticación (AV:N, PR:N) permite deserializar datos arbitrarios en .NET, ejecutando código remoto. CVSS crítico confirma RCE.
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (2)
CWE
- CWE-502
- CWE-502
Referencias
- http://packetstormsecurity.com/files/175677/AjaxPro-Deserialization-Remote-Code-Execution.html
- https://github.com/michaelschwarz/Ajax.NET-Professional/commit/b0e63be5f0bb20dfce507cb8a1a9568f6e73de57
- https://snyk.io/vuln/SNYK-DOTNET-AJAXPRO2-1925971
- http://packetstormsecurity.com/files/175677/AjaxPro-Deserialization-Remote-Code-Execution.html
- https://github.com/michaelschwarz/Ajax.NET-Professional/commit/b0e63be5f0bb20dfce507cb8a1a9568f6e73de57
- https://snyk.io/vuln/SNYK-DOTNET-AJAXPRO2-1925971
- https://blog.talosintelligence.com/uat-10147-chinese-speaking-adversary-integrates-agentic-ai-into-post-compromise-operations/
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-23758
JSON original (NVD)
Mostrar
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