CVE-2026-3549 (GCVE-0-2026-3549)

Vulnerability from cvelistv5 – Published: 2026-03-19 20:09 – Updated: 2026-03-19 20:09
VLAI?
Title
ECH parsing heap buffer overflow
Summary
Heap Overflow in TLS 1.3 ECH parsing. An integer underflow existed in ECH extension parsing logic when calculating a buffer length, which resulted in writing beyond the bounds of an allocated buffer. Note that in wolfSSL, ECH is off by default, and the ECH standard is still evolving.
Severity ?
8.3 (High)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:H/SC:L/SI:L/SA:L
CWE
  • CWE-122 - Heap-based buffer overflow
Assigner
References
Impacted products
Vendor Product Version
wofSSL wolfSSL Affected: 0 , < 5.9.0 (semver)
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Credits
Oleh Konko for independently reporting after internal wolfSSL findings and testing wolfSSL's fix
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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