CriticalCVECVE-2026-16516
wolfSSH 1.6.0 Fixes 5 Security Flaws Including Critical MITM Host Key Verification Bypass
Cyber Security News·Source published ·1 min read
What happened?
wolfSSL has released wolfSSH 1.6.0 to fix five security flaws, including a critical host key verification bypass that could let an attacker impersonate an SSH server. Published on October 6, 2026, the update addresses Windows privilege escalation, unauthenticated key exchange abuse, unauthorized forwarding channels, and an SFTP memory corruption bug. The release rates one flaw critical, one high, and three medium. The most serious issue, CVE-2026-16516, affects wolfSSH through version 1.5.0.
Key details
- wolfSSL released wolfSSH 1.6.0 to address five security vulnerabilities with varying severity levels.
- Windows privilege escalation occurs due to shared authentication context with logon tokens across connections.
- Forwarding channel requests accepted without checking application forwarding policy in enabled builds.
- SFTP path handling flaw allows stack buffer overflow with crafted paths on non-Windows builds.
- Version 1.6.0 enables strict key exchange by default and enforces minimum RSA key size of 2048 bits.
Affected
- wolfSSH through version 1.5.0 affected by CVE-2026-16516 host key verification bypass.
- wolfSSHd on Windows versions 1.4.15 through 1.5.0 affected by privilege escalation flaw.
- Versions 1.2.0 through 1.5.0 affected by Diffie-Hellman group exchange message handling flaw.
- Versions 1.5.0 affected by expensive prime checks in Diffie-Hellman group exchange.
- Non-Windows builds versions 1.4.11 through 1.5.0 affected by SFTP memory corruption.
Summarised by SecOraLens from Cyber Security News. Always read the original source before acting. How SecOraLens verifies advisories.