CVE-2026-56864
A malicious GOSUMDB was capable of serving arbitrary module content not contained within the transparency log. This attack allows for a coordinating GOPROXY and GOSUMDB to serve a client malicious module content that cannot be detected by evaluating the transparency log. In order to determine if you have been affected: rm -r go.sum go.work.sum vendor/ && go mod tidy
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- Puntuación base: 7.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.30%
- Percentil entre todas las CVEs puntuadas: 20
- 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 access85 % - Impacto principal
T1553.006Code Signing Policy Modificationdefense impairment80 % - Impacto secundario
T1195.001Compromise Software Dependencies and Development Toolsinitial access75 %
AV:N/AC:L/PR:N permite T1190. GOSUMDB malicioso sirve contenido de módulos no verificado (T1553.006: bypass de validación criptográfica). La cadena GOPROXY+GOSUMDB coordinados es ataque a la cadena de suministro (T1195.001).
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)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-347
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-56864",
"cveTags": [],
"metrics": {
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{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-56864",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "partial"
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],
"version": "2.0.3",
"timestamp": "2026-08-14T16:16:37.911009Z"
}
}
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"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "NONE",
"privilegesRequired": "NONE",
"confidentialityImpact": "HIGH"
},
"impactScore": 3.6,
"exploitabilityScore": 3.9
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"affected": [
{
"source": "security@golang.org",
"affectedData": [
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"vendor": "Go toolchain",
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"versions": [
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"status": "affected",
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"published": "2026-08-13T22:17:22.677",
"references": [
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"url": "https://go.dev/cl/815000",
"source": "security@golang.org"
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{
"url": "https://go.dev/cl/815020",
"source": "security@golang.org"
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"source": "security@golang.org"
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{
"url": "https://groups.google.com/g/golang-announce/c/94pEornpRlI",
"source": "security@golang.org"
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{
"url": "https://pkg.go.dev/vuln/GO-2026-6180",
"source": "security@golang.org"
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"weaknesses": [
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"description": [
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"value": "A malicious GOSUMDB was capable of serving arbitrary module content not contained within the transparency log. This attack allows for a coordinating GOPROXY and GOSUMDB to serve a client malicious module content that cannot be detected by evaluating the transparency log. In order to determine if you have been affected: rm -r go.sum go.work.sum vendor/ && go mod tidy"
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"lastModified": "2026-09-03T16:37:52.170",
"sourceIdentifier": "security@golang.org"
}