CVE-2026-3849 — Buffer Overflow in HPKE via Oversized ECH Config

CVE-2026-3849

Buffer Overflow in HPKE via Oversized ECH Config PUBLISHED

Description (CNA)

Stack Buffer Overflow in wc_HpkeLabeledExtract via Oversized ECH Config. A vulnerability existed in wolfSSL 5.8.4 ECH (Encrypted Client Hello) support, where a maliciously crafted ECH config could cause a stack buffer overflow on the client side, leading to potential remote execution and client program crash. This could be exploited by a malicious TLS server supporting ECH. Note that ECH is off by default, and is only enabled with enable-ech.

Affected (CNA)

Vendor / product	Versions
wolfSSL Inc. / wolfSSL	affected v5.6.0-stable through v5.8.4-stable

CWE

CWE-787

References

https://github.com/wolfSSL/wolfssl/pull/9737

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.