THREATOPS

THREAT OPS › Threat News › [NVD] CVE-2026-67336 (HIGH 8.7) — better-auth versions before 1.6.11 contain insecure cryptographic defaults in the oidcProvider and mcp plugins that advertise the none algorithm and accept plain PKCE by default. Attackers can exploit algorithm negotiation to accept unsigned tokens or intercept authorization code

[NVD] CVE-2026-67336 (HIGH 8.7) — better-auth versions before 1.6.11 contain insecure cryptographic defaults in the oidcProvider and mcp plugins that advertise the none algorithm and accept plain PKCE by default. Attackers can exploit algorithm negotiation to accept unsigned tokens or intercept authorization code

mednvdPublished 2026-08-01

CVE-2026-67336 CVSS: 8.7 HIGH Published: 2026-08-01T13:17:04.557

better-auth versions before 1.6.11 contain insecure cryptographic defaults in the oidcProvider and mcp plugins that advertise the none algorithm and accept plain PKCE by default. Attackers can exploit algorithm negotiation to accept unsigned tokens or intercept authorization codes when PKCE plain is used instead of the required S256

Indicators of compromise

CVE-2026-67336cve

Original source: https://nvd.nist.gov/vuln/detail/CVE-2026-67336