CVE Tracker

CVE-2026-16516

wolfSSH does not validate that the ECDSA curve identifier in a KEXDH_REPLY host key blob matches the algorith…

wolfSSH does not validate that the ECDSA curve identifier in a KEXDH_REPLY host key blob matches the algorithm negotiated during key exchange. In ParseECCPubKey() (src/internal.c), the blob's algorithm string is used to derive the curve via NameToId/wcPrimeForId without checking against the negotiated ssh->handshake->pubKeyId, and the RFC 5656 curve identifier string is discarded via GetSkip() rather than compared. An active network man-in-the-middle attacker can substitute a host key blob containing a different ECDSA curve, causing the client to import the key on the wrong curve. Because the attacker controls the private key for the substituted curve, signature verification passes. Exploitation requires an active MitM position and a lax public key check callback (e.g., TOFU, algorithm-name-only check, or fingerprint match against the parsed key).

Vendor

wolfssh

Product

wolfssh

CVSS 3.1

7.4 (high), scored by NVD (primary)CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

CVSS 4.0

9 (critical), scored by facts@wolfssl.comCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:L/SI:H/SA:N/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

CWE

CWE-345

Published

2026-10-07

NVD modified

2026-10-13

NVD status

Analyzed

Not in the CISA KEV catalogue at the last update.

Data last updated 18 Oct 2026. Sources: NVD API 2.0, FIRST EPSS. Links: NVD, CISA KEV. Metadata only. ThreatWire does not host exploit code.