{"schemaVersion":3,"id":"CVE-2026-53538","aliases":["GHSA-6jv3-5f52-599m","PYSEC-2026-3037","UBUNTU-CVE-2026-53538","DEBIAN-CVE-2026-53538","CGA-2hf7-x5jh-r62m","CGA-xhv6-p3x9-f695","CGA-4vjm-w5rh-955v","CGA-55f9-9m44-78c6","CGA-592w-7985-mw7g","CGA-cmc2-wfv9-j293","CGA-cq6j-qxrr-ph6g","CGA-p9jr-pjmm-x2vq","CGA-r466-hg37-xqc7","CGA-v4c2-hqm4-98xx","CGA-vj9c-hchx-x33r","CGA-vv8w-jgc2-4rxr","CGA-vvjv-2xf3-6fxw","CGA-wg94-j9j7-jcj5","CGA-xg2v-9qh7-c3h5","CGA-xv88-5w54-94r2","CGA-xxw5-g6h9-qjg4"],"status":"published","duplicateOf":null,"title":null,"description":"Python-Multipart is a streaming multipart parser for Python. Prior to 0.0.30, QuerystringParser treated ; as a field separator in application/x-www-form-urlencoded bodies, in addition to &. The WHATWG URL standard, modern browsers, and Python's urllib.parse (since the CVE-2021-23336 fix) treat only & as a separator. 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