Medium severity · published Oct 26, 2026
CVE-2026-114216
Chunk extensions accept bare LF and CR, enabling request smuggling in Bandit
New
6.3
CVSS
0.6%
EPSS
No
On KEV
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 49% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
BA
bandit · mtrudel
1.12.4 before 1.14.0; c31e9e3c76dcbfc239a96eabed5341ced7885ae5 before 220b9dfd27f9a21305be2afc75cbe585ddc24e7a · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-114216
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-114216
cna.erlef.org
https://cna.erlef.org/cves/CVE-2026-114216.html
github.com
https://github.com/mtrudel/bandit/commit/220b9dfd27f9a21305be2afc75cbe585ddc24e7a
github.com
https://github.com/mtrudel/bandit/commit/c31e9e3c76dcbfc239a96eabed5341ced7885ae5
github.com
https://github.com/mtrudel/bandit/security/advisories/GHSA-w5wc-g2hc-g7m2
osv.dev
https://osv.dev/vulnerability/EEF-CVE-2026-114216
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