CVE-2026-111103

What it is

Improper Cleanup on Thrown Exception vulnerability in the HTTP/2 handler of mtrudel bandit allows an unauthenticated remote attacker to bypass per-connection resource limits via a single TCP write that carries several frames, one of which raises a stream error. When a frame raises StreamError partway through a chunk, Bandit.HTTP2.Handler.handle_data/3 sends RST_STREAM and continues with the connection state from before the chunk, dropping the rest of it. Streams opened by earlier frames in the chunk keep running their Plug calls, but the stream counts, last_stream_id, the rapid-reset timestamps, the HPACK decoder state and the buffer roll back, so max_concurrent_streams, max_requests and the rapid-reset limiter never see those streams. A client that sends one HEADERS frame more than max_concurrent_streams in each write has the extra refused and the others forgotten: with a limit of 10, five such writes run 50 Plug calls at once. This issue affects bandit: from 1.9.0 before 1.14.0.

At a glance

Exploitability

Can be exploited over the network without logging in. High risk of service disruption.

Exploit odds

0.6% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-10-23 10:30 UTC ReservedThe CVE id was reserved by its CNA
2. 2026-10-26 14:16 UTC PublishedDisclosed publicly on CVE.org and NVD
3. 2026-10-26 16:59 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.6% in the next 30 days (EPSS).
• Severity: 8.2 HIGH (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2026-10-26 14:16 UTC

Last modified

2026-10-26 16:59 UTC

Exploit probability

0.6% · EPSS, next 30 days

Weakness

CWE-460

Record status

Awaiting Analysis

Attack profile CVSS 4.0 · 8.2

Attack vector

Network

Complexity

Low

Attack requirements

Present

Privileges needed

None

User interaction

None

Confidentiality

None

Integrity

None

Availability

High

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2026-111103.md and follow it. Check whether this project is affected by CVE-2026-111103. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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