CVE-2026-3849
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 products
- Wolfssl
- Wolfssl
- < 5.9.0
- CVSS 3.1
- 9.8 CRITICAL
- EPSS
- 0.4% (36th percentile)
- Weakness
- CWE-787
- NVD status
- Analyzed
- Published
- 2026-03-19
CVE-2026-3849 at NVD
No indexed exploits for CVE-2026-3849 yet
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No exploit for CVE-2026-3849 has been indexed yet. Our index is built from live traffic and upstream syncs, so this page can only say what it knows — not that no exploit exists.