Chunk extensions accept bare LF and CR, enabling request smuggling in Bandit
Impact
Bandit versions 1.12.4 before 1.14.0 have an HTTP Request Smuggling vulnerability, allowing an unauthenticated remote attacker to smuggle a second request past a front-end proxy via a chunk extension with a bare LF. This issue affects deployments with a proxy in front of Bandit. The weakness is due to inconsistent interpretation of HTTP requests.
Summarized by @cf/meta/llama-3.3-70b-instruct-fp8-fast. Verify details against the original sources.What to do
Where the front-end proxy can reach Bandit over HTTP/2, disable HTTP/1 with http_1_options: [enabled: false], so that the chunked body reader never runs.
Affected packages
Affected products
Vendor version evidence. Product records are separate from automatic dependency matching.
mtrudel · EEF
bandit
1 range
mtrudel · EEF
bandit
Package identity
pkg:hex/banditExplore bandit →Identity supplied by EEF. Version matching requires compatible range evidence.
Compare with this publisher’s ranges. This does not inspect your installation.
affected
1.12.4 → before 1.14.0
semver versions
Other versions: unaffected
Product identifiers (CPE)
cpe:2.3:a:mtrudel:bandit:*:*:*:*:*:*:*:*mtrudel · EEF
bandit
1 range
mtrudel · EEF
bandit
Package identity
pkg:github/mtrudel/banditIdentity supplied by EEF. Version matching requires compatible range evidence.
Compare with this publisher’s ranges. This does not inspect your installation.
affected
c31e9e3c76dcbfc239a96eabed5341ced7885ae5 → before 220b9dfd27f9a21305be2afc75cbe585ddc24e7a
git versions
Other versions: unaffected
Product identifiers (CPE)
cpe:2.3:a:mtrudel:bandit:*:*:*:*:*:*:*:*Original source 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.
Inside the record
Evidence available
Describes the evidence in this view, not whether the product is safe.
Original records
CVE-2026-114216View the latest unmodified CVE JSON from the official source. It may be newer than this imported page.
cve.new JSON →Underlying weaknesses
The source’s classification of what caused the vulnerability.
Environment requirements
These conditions apply together as specified by the publisher. A matching product name alone does not establish exposure.
EEF · platform conditions
All conditions must hold
Any condition may hold
Vulnerable product
cpe:2.3:a:mtrudel:bandit:*:*:*:*:*:*:*:*From (inclusive): 1.12.4
Before: 1.14.0
Original applicability statements
[
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:mtrudel:bandit:*:*:*:*:*:*:*:*",
"versionEndExcluding": "1.14.0",
"versionStartIncluding": "1.12.4",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
],
"operator": "AND"
}
]Contributing organizations · 2
Assigning organization
Additional data publisher
What changed
Follow changesLarge field values are marked as truncated previews. Original source snapshots remain retained.