CVE-2026-93475
The X.509 parser in NetX Secure accepts an RSA public key of any size, but every signature-verification path decrypts into fixed-size buffers dimensioned for the `NX_CRYPTO_MAX_RSA_MODULUS_SIZE` default of 4096 bits. A certificate carrying a larger modulus drives an out-of-bounds write past a file-scope static during ordinary certificate-chain verification.
It is reachable pre-authentication. The issuer used for the crypto operation is looked up in the remote, peer-supplied store before the trusted store, so the attacker supplies the oversized key themselves as an intermediate in the chain they present. It triggers on a TLS or DTLS client verifying a malicious server's chain, and on a server performing client-certificate authentication.
CVSS
- Base score
- 9.3
- Version
- 4.0
- Vector
- CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/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
Exploitation probability (EPSS)
FIRST hasn't scored this CVE yet (usual for very recent or rejected CVEs).
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
ATT&CK techniques
How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.
- Exploitation
T1190Exploit Public-Facing Applicationinitial access90 % - Primary impact
T1499Endpoint Denial of Serviceimpact40 % - Secondary impact
T1565Data Manipulationimpact30 %
Vector AV:N/PR:N/UI:N y escritura fuera de límites (CWE-787) en verificación de cadena; el texto no menciona ejecución de comandos, así que no se asigna T1059 pese a la pista.
Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.
ATT&CK mitigations that cover these techniques
Affected technologies (1)
⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.
CWEs
- CWE-787, CWE-1284
References
Raw JSON (NVD)
Show
{
"id": "CVE-2026-93475",
"cveTags": [],
"metrics": {
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"timestamp": "2026-10-20T17:02:43.642743Z"
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"vulnerabilityResponseEffort": "NOT_DEFINED",
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"affectedData": [
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"version": "0",
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"published": "2026-10-20T16:17:17.520",
"references": [
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"url": "https://github.com/eclipse-threadx/netxduo/security/advisories/GHSA-rcv5-vfff-25gh",
"source": "emo@eclipse.org"
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"value": "The X.509 parser in NetX Secure accepts an RSA public key of any size, but every signature-verification path decrypts into fixed-size buffers dimensioned for the `NX_CRYPTO_MAX_RSA_MODULUS_SIZE` default of 4096 bits. A certificate carrying a larger modulus drives an out-of-bounds write past a file-scope static during ordinary certificate-chain verification.\n\n\n\nIt is reachable pre-authentication. The issuer used for the crypto operation is looked up in the remote, peer-supplied store before the trusted store, so the attacker supplies the oversized key themselves as an intermediate in the chain they present. It triggers on a TLS or DTLS client verifying a malicious server's chain, and on a server performing client-certificate authentication."
}
],
"lastModified": "2026-10-20T18:17:23.060",
"sourceIdentifier": "emo@eclipse.org"
}