Eclipse ThreadX up to 6.5.1.202602 X.509 Parser out-of-bounds write

Summaryinfo

A vulnerability, which was classified as very critical, was found in Eclipse ThreadX up to 6.5.1.202602. Impacted is an unknown function of the component X.509 Parser. Such manipulation leads to out-of-bounds write. This vulnerability is referenced as CVE-2026-93475. It is possible to launch the attack remotely. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Eclipse ThreadX up to 6.5.1.202602. It has been rated as very critical. Affected by this issue is some unknown functionality of the component X.509 Parser. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. Using CWE to declare the problem leads to CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-93475 since 09/23/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 10/20/2026).

Upgrading to version 6.5.2.202603 eliminates this vulnerability.

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Productinfo

Vendor

• Eclipse

Name

• ThreadX

Version

• 6.5.1.202602

License

• open-source

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CPE 2.2info

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