Description

In TLSX_EchChangeSNI, the ctx->extensions branch set extensions unconditionally even when TLSX_Find returned NULL. This caused TLSX_UseSNI to attach the attacker-controlled publicName to the shared WOLFSSL_CTX when no inner SNI was configured. TLSX_EchRestoreSNI then failed to clean it up because its removal was gated on serverNameX != NULL. The inner ClientHello was sized before the pollution but written after it, causing TLSX_SNI_Write to memcpy 255 bytes past the allocation boundary.

INFO

Published Date :

2026-04-09T22:35:39.437Z

Last Modified :

2026-04-10T17:58:51.312Z

Source :

wolfSSL
AFFECTED PRODUCTS

The following products are affected by CVE-2026-5503 vulnerability.

Vendors Products
Wolfssl
  • Wolfssl
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-5503.

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