PT-2026-52571 · Wolfssl · Wolfssl

Published

2026-06-25

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Updated

2026-06-25

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CVE-2026-55958

CVSS v4.0

8.3

High

VectorAV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/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
Out-of-bounds write in the Renesas TSIP TLS 1.3 transcript buffer. In tsip StoreMessage() the capacity check guarding the fixed message bag (MSGBAG SIZE) sets an error code but fails to return, so execution falls through to an XMEMCPY that writes past the end of the buffer once the accumulated TLS 1.3 handshake transcript exceeds MSGBAG SIZE (8 KB), corrupting adjacent heap state and potentially causing a remote denial of service crash. The bag is sized to hold a normal handshake, so this is reached only by an unusually large but valid certificate chain, or by a malicious or man-in-the-middle server sending an oversized handshake message to a client that does not strictly verify the chain. This only affects builds using the Renesas TSIP TLS port (WOLFSSL RENESAS TSIP TLS) as a TLS 1.3 client on Renesas MCUs with TSIP hardware enabled, and is rated High within those builds. All other configurations are unaffected.

Fix

Memory Corruption

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Weakness Enumeration

Related Identifiers

CVE-2026-55958

Affected Products

Wolfssl