GHSA-g7jq-j257-rww2 OpenStack Swift: s3api middleware enters an infinite loop when processing a truncated aws-chunked PUT request body

• PyPI swift: >= 2.36.0, <= 2.36.1 (no fix yet) • PyPI swift: >= 2.37.0, <= 2.37.1 (no fix yet)

In OpenStack Swift before 2.36.2 and 2.37.2, s3api middleware enters an infinite loop when processing a truncated aws-chunked PUT request body. The StreamingInput class repeatedly appends an empty buffer and re-reads, causing the proxy-server worker handling the request to become permanently unresponsive with increasing CPU and memory consumption. An authenticated attacker can systematically exhaust all proxy-server workers, resulting in denial of service. The defect was introduced in Swift 2.36.0.