CVE-2026-3706
Estado: AplazadaBaja (1.7)—
A vulnerability was determined in mkj Dropbear up to 2025.89. Impacted is the function unpackneg of the file src/curve25519.c of the component S Range Check. This manipulation causes improper verification of cryptographic signature. The attack can be initiated remotely. The attack is considered to have high complexity. The exploitability is considered difficult. The actual existence of this vulnerability is currently in question. Patch name: fdec3c90a15447bd538641d85e5a3e3ac981011d. To fix this issue, it is recommended to deploy a patch. The project maintainer explains: "Signature Malleability is not exploitable in SSH protocol. (...) [A] PoC doesn't exist for SSH implementation, but rather it's against the internal API."
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Puntuación base: 1.7
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.19%
- Percentil entre todas las CVEs puntuadas: 8
- 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).
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-345, CWE-347
Referencias
- https://github.com/mkj/dropbear/
- https://github.com/mkj/dropbear/commit/fdec3c90a15447bd538641d85e5a3e3ac981011d
- https://github.com/mkj/dropbear/issues/406
- https://github.com/mkj/dropbear/pull/407
- https://github.com/str4d/ed25519-java/issues/82#issue-727629226
- https://vuldb.com/?ctiid.349652
- https://vuldb.com/?id.349652
- https://vuldb.com/?submit.765933
- https://github.com/mkj/dropbear/issues/406
JSON original (NVD)
Mostrar
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"affectedData": [
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"modules": [
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{
"status": "affected",
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"status": "affected",
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"status": "affected",
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],
"published": "2026-03-08T05:16:31.847",
"references": [
{
"url": "https://github.com/mkj/dropbear/",
"source": "cna@vuldb.com"
},
{
"url": "https://github.com/mkj/dropbear/commit/fdec3c90a15447bd538641d85e5a3e3ac981011d",
"source": "cna@vuldb.com"
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{
"url": "https://github.com/mkj/dropbear/issues/406",
"source": "cna@vuldb.com"
},
{
"url": "https://github.com/mkj/dropbear/pull/407",
"source": "cna@vuldb.com"
},
{
"url": "https://github.com/str4d/ed25519-java/issues/82#issue-727629226",
"source": "cna@vuldb.com"
},
{
"url": "https://vuldb.com/?ctiid.349652",
"source": "cna@vuldb.com"
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{
"url": "https://vuldb.com/?id.349652",
"source": "cna@vuldb.com"
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{
"url": "https://vuldb.com/?submit.765933",
"source": "cna@vuldb.com"
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{
"url": "https://github.com/mkj/dropbear/issues/406",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
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],
"vulnStatus": "Deferred",
"weaknesses": [
{
"type": "Secondary",
"source": "cna@vuldb.com",
"description": [
{
"lang": "en",
"value": "CWE-345"
},
{
"lang": "en",
"value": "CWE-347"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "A vulnerability was determined in mkj Dropbear up to 2025.89. Impacted is the function unpackneg of the file src/curve25519.c of the component S Range Check. This manipulation causes improper verification of cryptographic signature. The attack can be initiated remotely. The attack is considered to have high complexity. The exploitability is considered difficult. The actual existence of this vulnerability is currently in question. Patch name: fdec3c90a15447bd538641d85e5a3e3ac981011d. To fix this issue, it is recommended to deploy a patch. The project maintainer explains: \"Signature Malleability is not exploitable in SSH protocol. (...) [A] PoC doesn't exist for SSH implementation, but rather it's against the internal API.\""
},
{
"lang": "es",
"value": "Se determinó una vulnerabilidad en mkj Dropbear hasta 2025.89. La función unpackneg del archivo src/curve25519.c del componente S Range Check se ve afectada. Esta manipulación provoca una verificación incorrecta de la firma criptográfica. El ataque puede iniciarse de forma remota. Se considera que el ataque tiene una complejidad alta. La explotabilidad se considera difícil. El exploit ha sido divulgado públicamente y puede ser utilizado. Nombre del parche: fdec3c90a15447bd538641d85e5a3e3ac981011d. Para solucionar este problema, se recomienda desplegar un parche."
}
],
"lastModified": "2026-06-17T10:44:02.720",
"sourceIdentifier": "cna@vuldb.com"
}