Description
Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') vulnerability in the HTTP/1.1 chunked body reader of mtrudel bandit allows an unauthenticated remote attacker to smuggle a second request past a front-end proxy via a chunk extension that contains a bare LF.
The chunked reader in lib/bandit/http1/socket.ex takes the chunk-size line to be everything up to the first CRLF and discards everything after ; without checking it against the RFC 9112 chunk-ext grammar, so bare LF, bare CR and other control bytes pass. A proxy that ends the size line at a bare LF reads 2;\nxx\r\n40\r\n... as one request whose second chunk holds a GET /admin, while Bandit ends the body early and dispatches GET /admin as a separate pipelined request. Deployments without such a proxy in front of Bandit are not affected.
This issue affects bandit: from 1.12.4 before 1.14.0.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| mtrudel | bandit | 1.12.4 – < 1.14.0 | 1.14.0 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | bandit | No fix yet | — |
| Ubuntu 26.04 LTS | bandit | No fix yet | — |
| Ubuntu 24.04 LTS | bandit | No fix yet | — |
| Ubuntu 22.04 LTS | bandit | No fix yet | — |
| Ubuntu 20.04 LTS | bandit | No fix yet | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | bandit | No fix yet | — |
| Ubuntu 16.04 LTS | bandit | No fix yet | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Hex | bandit | >= 1.12.4, < 1.14.0 | 1.14.0 | EEF-CVE-2026-114216 |
References
- Chunk extensions accept bare LF and CR, enabling request smuggling in Bandit vendor-advisory related
- EEF CNA record for CVE-2026-114216 related
- OSV record EEF-CVE-2026-114216 related
- Introducing commit c31e9e3 in mtrudel/bandit related
- Fix commit 220b9df in mtrudel/bandit patch