CVE-2026-54431
Estado: AplazadaMedia (5.1)—
In liboauth2 the Demonstrating Proof-of-Possession (DPoP) verifier accepts a proof whose JSON Web Key (jwk) header contains private key material. RFC 9449 section 4.3 step 7 requires the verifier to reject such a proof but oauth2_token_verify() function returns success for a malformed DPoP proof that embeds the private Elliptic Curve (EC) key in the header.
This issue was fixed in version 2.3.0
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/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: 5.1
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.18%
- Percentil entre todas las CVEs puntuadas: 7
- 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-358
Referencias
JSON original (NVD)
Mostrar
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"role": "CISA Coordinator",
"options": [
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"exploitation": "none"
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{
"automatable": "no"
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"version": "2.0.3",
"timestamp": "2026-07-02T12:16:34.432412Z"
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"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/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",
"exploitMaturity": "NOT_DEFINED",
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"userInteraction": "NONE",
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"vulnIntegrityImpact": "NONE",
"integrityRequirement": "NOT_DEFINED",
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"defaultStatus": "unaffected",
"programRoutines": [
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"published": "2026-07-02T11:16:17.123",
"references": [
{
"url": "https://cert.pl/en/posts/2026/07/CVE-2026-54430",
"source": "cvd@cert.pl"
},
{
"url": "https://github.com/OpenIDC/liboauth2",
"source": "cvd@cert.pl"
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{
"url": "https://github.com/OpenIDC/liboauth2/commit/c0b57152ed6a0af33aeb04a60bd7f5bff5ab8800",
"source": "cvd@cert.pl"
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"description": [
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"descriptions": [
{
"lang": "en",
"value": "In liboauth2 the Demonstrating Proof-of-Possession (DPoP) verifier accepts a proof whose JSON Web Key (jwk) header contains private key material. RFC 9449 section 4.3 step 7 requires the verifier to reject such a proof but oauth2_token_verify() function returns success for a malformed DPoP proof that embeds the private Elliptic Curve (EC) key in the header.\n\nThis issue was fixed in version 2.3.0"
}
],
"lastModified": "2026-07-02T17:43:14.020",
"sourceIdentifier": "cvd@cert.pl"
}