CVE-2026-3849
Buffer Overflow in HPKE via Oversized ECH Config
- State
- Published
- Severity
- 6.9 Medium
- Published
- Mar 19, 2026
- Updated
- Mar 25, 2026
- Reserved
- Mar 9, 2026
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 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 | wolfSSL |
Weaknesses
- CWE-787 Out-of-bounds Write
Affected Products
| Product | Versions |
|---|---|
wolfSSLwolfSSL Inc. |
|
References
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