FKIE_CVE-2026-26309

Vulnerability from fkie_nvd - Published: 2026-03-10 20:16 - Updated: 2026-03-11 16:14
Severity ?
5.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
5.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Summary
Envoy is a high-performance edge/middle/service proxy. Prior to 1.37.1, 1.36.5, 1.35.8, and 1.34.13, an off-by-one write in Envoy::JsonEscaper::escapeString() can corrupt std::string null-termination, causing undefined behavior and potentially leading to crashes or out-of-bounds reads when the resulting string is later treated as a C-string. This vulnerability is fixed in 1.37.1, 1.36.5, 1.35.8, and 1.34.13.
References
security-advisories@github.comhttps://github.com/envoyproxy/envoy/security/advisories/GHSA-56cj-wgg3-x943Vendor Advisory, Exploit
Impacted products
Vendor Product Version
envoyproxy envoy *
envoyproxy envoy *
envoyproxy envoy *
envoyproxy envoy 1.37.0
To clipboard 

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              "matchCriteriaId": "C4169052-E37B-4577-8689-4DA8D6AFF3F3",
              "versionEndExcluding": "1.34.13",
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  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Envoy is a high-performance edge/middle/service proxy. Prior to 1.37.1, 1.36.5, 1.35.8, and 1.34.13, an off-by-one write in Envoy::JsonEscaper::escapeString() can corrupt std::string null-termination, causing undefined behavior and potentially leading to crashes or out-of-bounds reads when the resulting string is later treated as a C-string. This vulnerability is fixed in 1.37.1, 1.36.5, 1.35.8, and 1.34.13."
    },
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      "value": "Envoy es un proxy de borde/intermedio/servicio de alto rendimiento. Antes de 1.37.1, 1.36.5, 1.35.8 y 1.34.13, una escritura por un byte en Envoy::JsonEscaper::escapeString() puede corromper la terminaci\u00f3n nula de std::string, causando comportamiento indefinido y potencialmente llevando a fallos o lecturas fuera de l\u00edmites cuando la cadena resultante es tratada posteriormente como una cadena C. Esta vulnerabilidad est\u00e1 corregida en 1.37.1, 1.36.5, 1.35.8 y 1.34.13."
    }
  ],
  "id": "CVE-2026-26309",
  "lastModified": "2026-03-11T16:14:20.730",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
          "version": "3.1"
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        "impactScore": 1.4,
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        "type": "Secondary"
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      "tags": [
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      "url": "https://github.com/envoyproxy/envoy/security/advisories/GHSA-56cj-wgg3-x943"
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  "vulnStatus": "Analyzed",
  "weaknesses": [
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          "value": "CWE-193"
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      "source": "security-advisories@github.com",
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    }
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}


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