{"affected":[{"package":{"ecosystem":"Hex","name":"bandit","purl":"pkg:hex/bandit"},"ranges":[{"events":[{"introduced":"0"},{"fixed":"1.11.0"}],"type":"SEMVER"}],"versions":["0.1.0","0.1.1","0.2.0","0.2.1","0.2.2","0.2.3","0.3.2","0.3.3","0.3.4","0.3.5","0.3.6","0.3.7","0.3.8","0.3.9","0.4.0","0.4.1","0.4.2","0.4.3","0.4.4","0.4.5","0.4.6","0.4.7","0.4.8","0.4.9","0.4.10","0.5.0","0.5.1","0.5.2","0.5.3","0.5.4","0.5.5","0.5.6","0.5.7","0.5.8","0.5.9","0.5.10","0.5.11","0.6.0","0.6.1","0.6.2","0.6.3","0.6.4","0.6.5","0.6.6","0.6.7","0.6.8","0.6.9","0.6.10","0.6.11","0.7.0","0.7.1","0.7.2","0.7.3","0.7.4","0.7.5","0.7.6","0.7.7","1.0.0-pre.1","1.0.0-pre.2","1.0.0-pre.3","1.0.0-pre.4","1.0.0-pre.5","1.0.0-pre.6","1.0.0-pre.7","1.0.0-pre.8","1.0.0-pre.9","1.0.0-pre.10","1.0.0-pre.11","1.0.0-pre.12","1.0.0-pre.13","1.0.0-pre.14","1.0.0-pre.15","1.0.0-pre.16","1.0.0-pre.17","1.0.0-pre.18","1.0.0","1.1.0","1.1.1","1.1.2","1.1.3","1.2.0","1.2.1","1.2.2","1.2.3","1.3.0","1.4.0","1.4.1","1.4.2","1.5.0","1.5.1","1.5.2","1.5.3","1.5.4","1.5.5","1.5.6","1.5.7","1.6.0","1.6.1","1.6.2","1.6.3","1.6.4","1.6.5","1.6.6","1.6.7","1.6.8","1.6.9","1.6.10","1.6.11","1.7.0","1.8.0","1.9.0","1.10.0","1.10.1","1.10.2","1.10.3","1.10.4"]},{"ranges":[{"events":[{"introduced":"0"},{"fixed":"1.11.0"}],"repo":"https://github.com/mtrudel/bandit","type":"GIT"}]}],"aliases":["GHSA-c67r-gc9j-2qf7","CVE-2026-39805"],"credits":[{"name":"Peter Ullrich","type":"FINDER"},{"name":"Mat Trudel","type":"REMEDIATION_DEVELOPER"},{"name":"Jonatan Männchen","type":"ANALYST"}],"database_specific":{"capec_ids":["CAPEC-33"],"cpe_ids":["cpe:2.3:a:mtrudel:bandit:*:*:*:*:*:*:*:*"],"cwe_ids":["CWE-444"]},"details":"## Summary\n\nInconsistent Interpretation of HTTP Requests vulnerability in mtrudel bandit allows HTTP request smuggling via duplicate Content-Length headers.\n\n'Elixir.Bandit.Headers':get_content_length/1 in lib/bandit/headers.ex uses List.keyfind/3, which returns only the first matching header. When a request contains two Content-Length headers with different values, Bandit silently accepts it, uses the first value to read the body, and dispatches the remaining bytes as a second pipelined request on the same keep-alive connection. RFC 9112 §6.3 requires recipients to treat this as an unrecoverable framing error.\n\nWhen Bandit sits behind a proxy that picks the last Content-Length value and forwards the request rather than rejecting it, an unauthenticated attacker can smuggle requests past edge WAF rules, path-based ACLs, rate limiting, and audit logging.\n\nThis issue affects bandit: before 1.11.0.","id":"EEF-CVE-2026-39805","modified":"2026-05-01T20:34:29.400Z","published":"2026-05-01T20:34:29.400Z","references":[{"type":"ADVISORY","url":"https://github.com/mtrudel/bandit/security/advisories/GHSA-c67r-gc9j-2qf7"},{"type":"WEB","url":"https://cna.erlef.org/cves/CVE-2026-39805.html"},{"type":"FIX","url":"https://github.com/mtrudel/bandit/commit/f2ca636eb6df385219957e8934e9fc6efa1630d1"},{"type":"PACKAGE","url":"https://hex.pm/packages/bandit"}],"related":[],"schema_version":"1.7.3","severity":[{"score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","type":"CVSS_V4"}],"summary":"CL.CL HTTP request smuggling via duplicate Content-Length in bandit","upstream":[]}