1sealsemantic last-mile verification

Research / Finding

ECH parsing heap buffer overflow

F-WOLFSSL-ECH-001

Public snapshot: 26 Sep 2026. Status, releases and attribution belong to each source below; none is inferred from another record.

Read the evidence · View in research browse

Recorded evidence

8.3high
CVE-2026-3549CVEwolfSSL/wolfssl

ECH parsing heap buffer overflow

Fixed in: wolfSSL 5.9.0

patched
details
Finding IDs
F-WOLFSSL-ECH-001
CVE
CVE-2026-3549
GHSA
GHSA-j2g5-52p7-mfpc
Status
patched
Fixed in
wolfSSL 5.9.0
Recorded credit
thanks to Oleh Konko (1seal) for testing (wolfSSL v5.9.0-stable release note)
CVSS vector
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVE registry state
PUBLISHED
CVE state checked

F-WOLFSSL-ECH-001: Memory safety. An ECH length underflow produces a heap out-of-bounds write. Reviewed 24 Sep 2026. Mechanism assessed by 1seal.

Mechanism source for F-WOLFSSL-ECH-001

Security area (1seal assessment): Memory safety. An ECH length underflow produces a heap out-of-bounds write. Reviewed 24 Sep 2026.

Clarify or correct this record privately. The email subject includes the finding ID. For an existing case, continue the agreed private thread. Do not post unpublished vulnerability details in public issues. Research disclosure policy.

How this page groups evidence

This identifier groups recorded evidence; it is not an additional CVE, independent-vulnerability count or guarantee of vendor confirmation. Fixed code, released versions, attribution and independent discovery are distinct claims. Absent metadata means not recorded, not disproved. Counting rules.