CVE-2026-93475

Out-of-bounds Write via an Unbounded RSA Modulus in NetX Secure X.509

State
Published
Severity
9.3 Critical
Published
Oct 20, 2026
Updated
Oct 20, 2026
Reserved
Sep 23, 2026

Read the record on cve.org

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.

Scores

CVSSScoreVectorSource
4.09.3 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:Neclipse

Weaknesses

  • CWE-787 Out-of-bounds Write
  • CWE-1284 Improper Validation of Specified Quantity in Input

Affected Products

ProductVersions
Eclipse ThreadX - NetX DuoEclipse Foundation
  • 6.5.1.202602 and earlierAffected
  • 6.5.2.202603Not affected

References

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.