GHSA-J6C9-X7QJ-28XF hono: AWS Lambda adapter merges multiple `Set-Cookie` headers into one value, dropping cookies on ALB single-header and Lattice

Summary On AWS Lambda, the ALB single-header response and the VPC Lattice v2 response join multiple Set-Cookie headers into one comma-separated value. Because commas also appear inside cookie attributes for example Expires dates, clients cannot split the value back into individual cookies and...

Improper Encoding or Escaping of Output

Overview hono is an Ultrafast web framework for the Edges Affected versions of this package are vulnerable to Improper Encoding or Escaping of Output in the AWS Lambda adapter's handling of multiple Set-Cookie headers. An attacker can cause clients to drop or misinterpret cookies by triggering...

hono: AWS Lambda adapter merges multiple `Set-Cookie` headers into one value, dropping cookies on ALB single-header and Lattice

Summary On AWS Lambda, the ALB single-header response and the VPC Lattice v2 response join multiple Set-Cookie headers into one comma-separated value. Because commas also appear inside cookie attributes for example Expires dates, clients cannot split the value back into individual cookies and...

PT-2026-49734

Name of the Vulnerable Software and Affected Versions Hono versions prior to 4.12.25 Description On AWS Lambda, the ALB single-header response and the VPC Lattice v2 response join multiple Set-Cookie headers into a single comma-separated value. According to RFC 6265, each cookie must be its own...