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CVE-2026-5244

Full vulnerability record from the local CVENow database.

Description

A vulnerability has been found in Cesanta Mongoose up to 7.20. This affects the function mg_tls_recv_cert of the file mongoose.c of the component TLS 1.3 Handler. Such manipulation of the argument pubkey leads to heap-based buffer overflow. The attack may be launched remotely. The exploit has been disclosed to the public and may be used. Upgrading to version 7.21 mitigates this issue. The name of the patch is 0d882f1b43ff2308b7486a56a9d60cd6dba8a3f1. It is advisable to upgrade the affected component. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.

Severity
MEDIUM
CVSS score
5.5 (v4.0)
Vulnerability status
Analyzed
Source identifier
Published
2026-04-02 08:16:28.683000
Last modified
2026-10-26 22:10:00.163000
View original CVE JSON
{
  "id": "CVE-2026-5244",
  "sourceIdentifier": "[email protected]",
  "published": "2026-04-02T08:16:28.683",
  "lastModified": "2026-10-26T22:10:00.163",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A vulnerability has been found in Cesanta Mongoose up to 7.20. This affects the function mg_tls_recv_cert of the file mongoose.c of the component TLS 1.3 Handler. Such manipulation of the argument pubkey leads to heap-based buffer overflow. The attack may be launched remotely. The exploit has been disclosed to the public and may be used. Upgrading to version 7.21 mitigates this issue. The name of the patch is 0d882f1b43ff2308b7486a56a9d60cd6dba8a3f1. It is advisable to upgrade the affected component. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product."
    },
    {
      "lang": "es",
      "value": "Una vulnerabilidad se ha encontrado en Cesanta Mongoose hasta la versión 7.20. Esto afecta a la función mg_tls_recv_cert del archivo mongoose.c del componente Gestor TLS 1.3. Dicha manipulación del argumento pubkey conduce a un desbordamiento de búfer basado en montículo. El ataque puede ser lanzado remotamente. El exploit ha sido divulgado al público y puede ser utilizado. La actualización a la versión 7.21 mitiga este problema. El nombre del parche es 0d882f1b43ff2308b7486a56a9d60cd6dba8a3f1. Es aconsejable actualizar el componente afectado. Se contactó al proveedor con antelación, respondió de manera muy profesional y rápidamente lanzó una versión corregida del producto afectado."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
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          "product": "Mongoose",
          "cpes": [
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          ],
          "modules": [
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          ],
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              "version": "7.1",
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              "version": "7.2",
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              "version": "7.10",
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              "version": "7.11",
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              "version": "7.12",
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              "version": "7.13",
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              "status": "affected"
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              "version": "7.15",
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              "version": "7.16",
              "status": "affected"
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            },
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              "version": "7.18",
              "status": "affected"
            },
            {
              "version": "7.19",
              "status": "affected"
            },
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              "version": "7.20",
              "status": "affected"
            },
            {
              "version": "7.21",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
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          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
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          "valueDensity": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
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    ],
    "cvssMetricV31": [
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  "configurations": [
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          "cpeMatch": [
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      "url": "https://github.com/cesanta/mongoose/",
      "source": "[email protected]",
      "tags": [
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    {
      "url": "https://github.com/cesanta/mongoose/commit/0d882f1b43ff2308b7486a56a9d60cd6dba8a3f1",
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      "source": "[email protected]",
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}