CVE-2026-103415

When a TLS 1.3 client processes a HelloRetryRequest, it copies the server's cookie into its second ClientHello without checking that the cookie fits in the outgoing packet. Both the length and the contents of that cookie come from the peer, and the write happens before certificate authentication completes, so a malicious or compromised server can overwrite memory past the caller supplied TLS packet buffer without presenting a certificate. Only the client path is affected.

CVSS

No CVSS.

References

Link	Resource
https://github.com/eclipse-threadx/netxduo/security/advisories/GHSA-5pv3-rhf5-gwgq
https://gitlab.eclipse.org/security/cve-assignment/-/work_items/357

Configurations

No configuration.

History

14 Oct 2026, 18:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-14 18:17

Updated : 2026-10-16 21:17

NVD link : CVE-2026-103415

Mitre link : CVE-2026-103415

CVE.ORG link : CVE-2026-103415

JSON object : View

Products Affected

No product.

CWE

CWE-787

Out-of-bounds Write

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