CVE-2026-28435
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.35.0, cpp-httplib (httplib.h) does not enforce Server::set_payload_max_length() on the decompressed request body when using HandlerWithContentReader (streaming ContentReader) with Content-Encoding: gzip (or other supported encodings). A small compressed payload can expand beyond the configured payload limit and be processed by the application, enabling a payload size limit bypass and potential denial of service (CPU/memory exhaustion). This vulnerability is fixed in 0.35.0.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 7.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.62%
- Percentil entre todas las CVEs puntuadas: 48
- Fecha de la puntuación: 6/10/2026
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).
🎯 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 access92 % - Impacto principal
T1499Endpoint Denial of Serviceimpact90 % - Impacto secundario
T1499.004Application or System Exploitationimpact75 %
Vector CVSS AV:N/AC:L/PR:N/UI:N indica explotación remota sin privilegios (T1190). CWE-400/409 y descripción confirman bypass de límite de payload con gzip, causando DoS por agotamiento de CPU/memoria (T1499, T1499.004 por resource exhaustion).
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 (1)
CWE
- CWE-400, CWE-409
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-28435",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-28435",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "poc"
},
{
"automatable": "yes"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2026-03-04T20:37:10.788317Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "security-advisories@github.com",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.5,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 3.9
}
]
},
"affected": [
{
"source": "security-advisories@github.com",
"affectedData": [
{
"vendor": "yhirose",
"product": "cpp-httplib",
"versions": [
{
"status": "affected",
"version": "< 0.35.0"
}
]
}
]
}
],
"published": "2026-03-04T20:16:19.983",
"references": [
{
"url": "https://github.com/yhirose/cpp-httplib/commit/c99d7472b5cf4869d3897b9afc9792063a3d15a8",
"tags": [
"Patch"
],
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-xvfx-w463-6fpp",
"tags": [
"Exploit",
"Mitigation",
"Vendor Advisory"
],
"source": "security-advisories@github.com"
}
],
"vulnStatus": "Analyzed",
"weaknesses": [
{
"type": "Secondary",
"source": "security-advisories@github.com",
"description": [
{
"lang": "en",
"value": "CWE-400"
},
{
"lang": "en",
"value": "CWE-409"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.35.0, cpp-httplib (httplib.h) does not enforce Server::set_payload_max_length() on the decompressed request body when using HandlerWithContentReader (streaming ContentReader) with Content-Encoding: gzip (or other supported encodings). A small compressed payload can expand beyond the configured payload limit and be processed by the application, enabling a payload size limit bypass and potential denial of service (CPU/memory exhaustion). This vulnerability is fixed in 0.35.0."
},
{
"lang": "es",
"value": "cpp-httplib es una librería HTTP/HTTPS multiplataforma de un solo archivo de cabecera C++11. Antes de la versión 0.35.0, cpp-httplib (httplib.h) no aplica Server::set_payload_max_length() en el cuerpo de la solicitud descomprimido al usar HandlerWithContentReader (ContentReader de transmisión) con Content-Encoding: gzip (u otras codificaciones compatibles). Una pequeña carga útil comprimida puede expandirse más allá del límite de carga útil configurado y ser procesada por la aplicación, lo que permite una omisión del límite de tamaño de la carga útil y una potencial denegación de servicio (agotamiento de CPU/memoria). Esta vulnerabilidad está corregida en la versión 0.35.0."
}
],
"lastModified": "2026-06-17T10:28:38.460",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:yhirose:cpp-httplib:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "27E6A328-789B-48B3-B888-23C091A0766D",
"versionEndExcluding": "0.35.0"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "security-advisories@github.com"
}