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CVE-2026-34040 is an authorization bypass in Moby and Docker Engine versions prior to 29.3.1. The AuthZ middleware can handle an oversized or specially crafted Docker API request body by forwarding an effectively bodyless request to an authorization plugin while the Docker daemon continues to process the complete body. AuthZ plugins that base allow-or-deny decisions on request-body inspection may consequently approve an operation that their policy would otherwise reject. The flaw is an incomplete fix for CVE-2024-41110.
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1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos.
This repository is a Python-based full lab PoC for CVE-2026-34040, targeting Docker/Moby AuthZ plugin bypass behavior when a Docker API request body exceeds 1 MB. The repository is small and focused: one executable script (poc.py), a standard-library-only requirements file, and several Markdown documents covering setup, demo flow, impact modes, troubleshooting, and publication notes. The main exploit logic is in poc.py. It manually crafts raw HTTP requests over the local UNIX socket /var/run/docker.sock rather than using the Docker SDK. The key capability is sending a container creation request with oversized JSON label padding ("padding" = "A" * (1024*1024+1)) so that an AuthZ plugin may fail to inspect the body while the Docker daemon still processes the original request. The script compares a normal request against an oversized one in check mode to determine whether the bypass is observable, expecting small requests to be blocked (HTTP 403) and oversized requests to reach daemon processing (HTTP 201 or possibly HTTP 404 if the image is missing). Beyond detection, the PoC includes multiple post-bypass impact modes. These include reading host files by creating a privileged container with the host root mounted read-only, writing a proof marker file on the host via chroot, executing user-supplied host commands in a lab, creating a long-lived privileged container for manual docker exec and chroot interaction, and a local-only reverse shell mode restricted to 127.0.0.1/localhost. The README and docs explicitly describe that the vulnerability itself is an authorization bypass, while file read and command execution are downstream impacts enabled by privileged container creation plus host bind mounts. Repository structure: README.md explains the vulnerability model, usage, and safety notes; docs/lab-setup.md lists prerequisites such as vulnerable Docker/Moby, AuthZ plugin, docker.sock access, and local alpine image; docs/impact-modes.md and docs/demo-script.md describe each demonstration path; docs/troubleshooting.md covers common failures like missing image or socket permissions. Overall, this is a real exploit PoC for local lab use, not merely a detector, and it is operational because it contains working payload paths for host file access and host command execution.
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66 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
One of multiple Docker Engine and bundled BuildKit vulnerabilities addressed by Debian DSA-6443; the advisory collectively describes potential privilege escalation, arbitrary host file access, and authorization-policy bypass.
A critical Docker Authorization bypass referenced as a related example of how prompt-injected autonomous AI agents could obtain dangerous Docker capabilities and then chain host-level flaws.
A high-impact local vulnerability affecting Docker CE on ZTE CGSL Main 7. Successful exploitation requires low privileges and could result in high confidentiality, integrity, and availability impact.
A historical Moby vulnerability mentioned for background context.
Query your assets running an affected version, and investigate the blast radius.
Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
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Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.