CVE-2020-36846
A buffer overflow, as described in CVE-2020-8927, exists in the embedded Brotli library. Versions of IO::Compress::Brotli prior to 0.007 included a version of the brotli library prior to version 1.0.8, where an attacker controlling the input length of a "one-shot" decompression request to a script can trigger a crash, which happens when copying over chunks of data larger than 2 GiB. It is recommended to update your IO::Compress::Brotli module to 0.007 or later. If one cannot update, we recommend to use the "streaming" API as opposed to the "one-shot" API, and impose chunk size limits.
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: 0.63%
- Percentil entre todas las CVEs puntuadas: 49
- 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).
🎯 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 access60 %
Inferido por reglas deterministas a partir del vector CVSS y la CWE. Solo orientativo.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (2)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
Referencias
- https://github.com/advisories/GHSA-5v8v-66v8-mwm7
- https://github.com/google/brotli/commit/223d80cfbec8fd346e32906c732c8ede21f0cea6
- https://github.com/google/brotli/pull/826
- https://github.com/timlegge/perl-IO-Compress-Brotli/blob/8b44c83b23bb4658179e1494af4b725a1bc476bc/Changes#L52
- https://nvd.nist.gov/vuln/detail/CVE-2020-8927
JSON original (NVD)
Mostrar
{
"id": "CVE-2020-36846",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2020-36846",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "total"
}
],
"version": "2.0.3",
"timestamp": "2025-05-30T14:40:47.592851Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 9.8,
"attackVector": "NETWORK",
"baseSeverity": "CRITICAL",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"exploitabilityScore": 3.9
}
]
},
"affected": [
{
"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
"affectedData": [
{
"repo": "https://github.com/timlegge/perl-IO-Compress-Brotli",
"vendor": "TIMLEGGE",
"product": "IO::Compress::Brotli",
"versions": [
{
"status": "affected",
"version": "0",
"lessThan": "0.007",
"versionType": "custom"
}
],
"packageName": "IO-Compress-Brotli",
"programFiles": [
"brotli/c/dec/bit_reader.h"
],
"collectionURL": "https://cpan.org/modules",
"defaultStatus": "unaffected"
}
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}
],
"published": "2025-05-30T01:15:20.950",
"references": [
{
"url": "https://github.com/advisories/GHSA-5v8v-66v8-mwm7",
"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
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{
"url": "https://github.com/google/brotli/commit/223d80cfbec8fd346e32906c732c8ede21f0cea6",
"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
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{
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"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
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{
"url": "https://github.com/timlegge/perl-IO-Compress-Brotli/blob/8b44c83b23bb4658179e1494af4b725a1bc476bc/Changes#L52",
"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
},
{
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-8927",
"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
}
],
"vulnStatus": "Deferred",
"descriptions": [
{
"lang": "en",
"value": "A buffer overflow, as described in CVE-2020-8927, exists in the embedded Brotli library. Versions of IO::Compress::Brotli prior to 0.007 included a version of the brotli library prior to version 1.0.8, where an attacker controlling the input length of a \"one-shot\" decompression request to a script can trigger a crash, which happens when copying over chunks of data larger than 2 GiB. It is recommended to update your IO::Compress::Brotli module to 0.007 or later. If one cannot update, we recommend to use the \"streaming\" API as opposed to the \"one-shot\" API, and impose chunk size limits."
},
{
"lang": "es",
"value": "Existe un desbordamiento de búfer, como se describe en CVE-2020-8927, en la librería Brotli integrada. Las versiones de IO::Compress::Brotli anteriores a la 0.007 incluían una versión de la librería Brotli anterior a la 1.0.8, donde un atacante que controle la longitud de entrada de una solicitud de descompresión única a un script puede provocar un fallo, lo cual ocurre al copiar fragmentos de datos de más de 2 GiB. Se recomienda actualizar el módulo IO::Compress::Brotli a la versión 0.007 o posterior. Si no se puede actualizar, recomendamos usar la API de streaming en lugar de la API única e imponer límites de tamaño de fragmentos."
}
],
"lastModified": "2026-06-17T03:16:19.050",
"sourceIdentifier": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
}