cvedb.io
CVE-2026-39805
UNKNOWN · CVSS n/a
EPSS exploitation probability: 0%
Published 2026-05-01T21:16:17.037 · Last modified 2026-06-17T10:42:36.490

Summary

Inconsistent Interpretation of HTTP Requests vulnerability in mtrudel bandit allows HTTP request smuggling via duplicate Content-Length headers. '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. When 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

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.