CVE-2026-26309
MEDIUM
CVSS 5.3
No EPSS data
Description
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.
CVSS details
EPSS
This CVE is not currently listed in the EPSS dataset.
Show JSON
{
"cve": {
"id": "CVE-2026-26309",
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"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
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"published": "2026-03-10T20:16:35.880",
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"description": [
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"value": "CWE-193"
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"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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{
"lang": "es",
"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."
}
],
"lastModified": "2026-03-11T16:14:20.730",
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