CVE-2026-93475
Received
Received - Intake
X.509 Parser Out-of-Bounds Write in NetX Secure
Vulnerability report for CVE-2026-93475, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-20
Last updated on: 2026-10-20
Assigner: Eclipse Foundation
Description
Description
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 Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| Eclipse | Foundation | Eclipse ThreadX - NetX Duo 0 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-1284 | The product receives input that is expected to specify a quantity (such as size or length), but it does not validate or incorrectly validates that the quantity has the required properties. |
| CWE-787 | The product writes data past the end, or before the beginning, of the intended buffer. |