cve.bz

CVE-2026-3849

6.9 mediumEPSS 0.5%

Medium (6.9) in wolfssl wolfssl. EPSS 0.5% chance of exploitation in the next 30 days.

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

CVSS 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

CVSS 3.1

9.8 critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
0.5% chance of exploitation in the next 30 days; higher than 39% of CVEs (scores of 2026-10-31)
CWE
CWE-787
Published
Modified
Record from
the NVD, synced

Affected

References

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