CVE-2026-105659
Received
Received - Intake
Uncontrolled Resource Consumption in Bandit
Vulnerability report for CVE-2026-105659, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-14
Last updated on: 2026-10-14
Assigner: EEF
Description
Description
Uncontrolled Resource Consumption vulnerability in mtrudel bandit allows an unauthenticated remote attacker to pin HTTP/2 stream processes indefinitely via a trickle of small WINDOW_UPDATE frames. A stream whose response outruns the connection or stream send window blocks until the peer grants more window, and each block carries a 15 second deadline. Both deadlines restart whenever the peer makes partial progress. Bandit.HTTP2.Connection.finish_data/5 re-queues a partially advanced send in pending_sends with a fresh expires_at, so every WINDOW_UPDATE on stream 0, and every SETTINGS frame, resets the clock. Bandit.HTTP2.Stream.send_data/3 recurses on each stream WINDOW_UPDATE and re-arms a fresh after read_timeout. A peer that grants a few bytes every few seconds keeps the blocked stream process, its Plug state and any resource it holds mid-response alive for as long as it keeps dripping, and repeats this across streams and connections to exhaust server processes and memory.
The two paths are independent. The stream-level block is reached on its own by widening the connection window with a large WINDOW_UPDATE on stream 0 and shrinking the per-stream window with a small SETTINGS_INITIAL_WINDOW_SIZE, so closing only the connection-level path leaves it exploitable.
This issue affects bandit: from 1.4.0 onward.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| mtrudel | bandit | 1.4.0 |
| mtrudel | bandit | fff06efe3be962b484bd4d3eb339372fda5a231f |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-400 | The product does not properly control the allocation and maintenance of a limited resource. |
