CVE-2026-3849 (GCVE-0-2026-3849)

Vulnerability from cvelistv5 – Published: 2026-03-19 20:29 – Updated: 2026-03-19 20:29
VLAI?
Title
Buffer Overflow in HPKE via Oversized ECH Config
Summary
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.
Severity ?
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/V:D/RE:M/U:Amber
CWE
Assigner
References
Impacted products
Vendor Product Version
wolfSSL Inc. wolfSSL Affected: v5.6.0-stable , ≤ v5.8.4-stable (git)
Create a notification for this product.
Credits
Haruto Kimura (Stella)
Show details on NVD website
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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