CVE-2026-114216

Chunk extensions accept bare LF and CR, enabling request smuggling in Bandit

MEDIUM
6.3
CVSS Score
Published: October 26, 2026 at 01:30 PM UTC
Updated: October 26, 2026 at 04:59 PM UTC
1 product affected across 1 vendorBandit

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Severity
MEDIUM6.3
Exploit prediction
EPSS 0.6%
SSVC
No known exploit

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

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

1.12.4c31e9e3c76dcbfc239a96eabed5341ced7885ae5

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6.3MEDIUMEEF
Vector?

Quick Info

StatusAWAITING ANALYSIS
CWE
CWE-444

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