CVE-2026-67336 (GCVE-0-2026-67336)
Vulnerability from cvelistv5
Published
2026-08-01 12:22
Modified
2026-08-03 15:23
Severity ?
9.4 (Critical) - CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N
8.7 (High) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N
CWE
  • CWE-327 - Use of a Broken or Risky Cryptographic Algorithm
Summary
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 method.
References
Impacted products
Vendor Product Version
better-auth better-auth Version: 0   ≤
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