Vulnerabilities in pkg:golang/github.com/moby/moby/v2

PACKAGE
Advisory Identifier: GHSA-x744-4wpc-v9h2
Advisory Summary

CVE-2026-34040 is a HIGH (CVSS 8.8) moby has authz plugin bypass vulnerability (CWE-288: Authentication Bypass Using an Alternate Path or Channel) affecting Github.com/moby/moby libraries in the Go ecosystem. The issue involves moby has authz plugin bypass when provided oversized request bodies. Remediation is available by upgrading affected packages to version 29.3.1, 2.0.0-beta.8.

5 Known Advisory Record(s)
Package Vulnerability Intelligence

pkg:golang/github.com/moby/moby/v2

5 Known Advisory Record(s)

Vulnerability advisories affecting package pkg:golang/github.com/moby/moby/v2. Select an advisory below to view technical details or fixes.

Advisory ID CVE / NVD Severity Summary
GHSA-x744-4wpc-v9h2 CVE-2026-34040 HIGH Moby has AuthZ plugin bypass when provided oversized request bodies
GHSA-rg2x-37c3-w2rh CVE-2026-42306 HIGH Docker: Race condition in docker cp allows bind mount redirection to host path
GHSA-vp62-88p7-qqf5 CVE-2026-41568 MODERATE Docker: Race condition in docker cp allows creation of arbitrary empty files on the host via symlink swap
GHSA-x86f-5xw2-fm2r CVE-2026-41567 HIGH Docker: `PUT /containers/{id}/archive` executes container binary on the host
GHSA-pxq6-2prw-chj9 CVE-2026-33997 MODERATE Moby has an Off-by-one error in its plugin privilege validation

CVE-2026-34040 at a Glance

CVE Identifier CVE-2026-34040
GHSA Identifier GHSA-x744-4wpc-v9h2
Severity HIGH
CVSS v3.1 Base Score 8.8
CWE Classification CWE-288: Authentication Bypass Using an Alternate Path or Channel
Affected Product Github.com/moby/moby
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 8.8

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H).

Attack Vector Local (AV:L)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Changed (S:C)
Confidentiality High (C:H)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2026-34040

To remediate this vulnerability, upgrade all affected Github.com/moby/moby dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

github.com/moby/moby fixed: 29.3.1
Upgrade github.com/moby/moby to 29.3.1
github.com/moby/moby/v2 fixed: 2.0.0-beta.8
Upgrade github.com/moby/moby/v2 to 2.0.0-beta.8
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

inspect dependencies for github.com/moby/moby

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-34040, inspect your project dependencies for Github.com/moby/moby:

inspect dependencies for github.com/moby/moby

Analyze the terminal output to locate any version of Github.com/moby/moby in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 29.3.1), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-288: Authentication Bypass Using an Alternate Path or Channel, where the product requires authentication, but the product has an alternate path or channel that does not require authentication. In Github.com/moby/moby, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

## Summary A security vulnerability has been detected that allows attackers to bypass [authorization plugins (AuthZ)](https://docs.docker.com/engine/extend/plugins_authorization/) under specific circumstances. The base likelihood of this being exploited is low. This is an incomplete fix for [CVE-2024-41110](https://github.com/moby/moby/security/advisories/GHSA-v23v-6jw2-98fq). ## Impact **If you don't use AuthZ plugins, you are not affected.** Using a specially-crafted API request, an attacker could make the Docker daemon forward the request to an authorization plugin without the body. The authorization plugin may allow a request which it would have otherwise denied if the body had been forwarded to it. Anyone who depends on authorization plugins that introspect the request body to make access control decisions is potentially impacted. ## Workarounds If unable to update immediately: - Avoid using AuthZ plugins that rely on request body inspection for security decisions. - Restrict access to the Docker API to trusted parties, following the principle of least privilege. ## Credits - 1seal / Oleh Konko ([@1seal](https://github.com/1seal)) - Cody (c@wormhole.guru) - Asim Viladi Oglu Manizada (@manizada) ## Resources - [CVE-2024-41110 / GHSA-v23v-6jw2-98fq](https://github.com/moby/moby/security/advisories/GHSA-v23v-6jw2-98fq)

CVE-2026-34040 Affected Github.com/moby/moby Versions

2 component(s)
Fixed Versions:
29.3.12.0.0-beta.8
Product / Package Ecosystem Affected Versions Fixed Version
github.com/moby/moby
Go
< 29.3.1
29.3.1
github.com/moby/moby/v2
Go
< 2.0.0-beta.8
2.0.0-beta.8

References

Frequently Asked Questions

What is CVE-2026-34040?
CVE-2026-34040 is a security vulnerability in Github.com/moby/moby involving Moby has AuthZ plugin bypass when provided oversized request bodies under CWE-288: Authentication Bypass Using an Alternate Path or Channel.
Which Github.com/moby/moby versions are affected?
Affected versions include releases prior to 29.3.1, 2.0.0-beta.8 across affected packages: github.com/moby/moby, github.com/moby/moby/v2.
What version fixes CVE-2026-34040?
Upgrading to 29.3.1, 2.0.0-beta.8 (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/moby/moby affected?
Yes, github.com/moby/moby is affected in releases prior to 29.3.1. Upgrade your dependency to 29.3.1 or later.
Is github.com/moby/moby/v2 affected?
Yes, github.com/moby/moby/v2 is affected in releases prior to 2.0.0-beta.8. Upgrade your dependency to 2.0.0-beta.8 or later.
What is the CVSS score of CVE-2026-34040?
CVE-2026-34040 has a CVSS v3.1 base score of 8.8 (HIGH) with vector string CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.
What CWE is associated with CVE-2026-34040?
CVE-2026-34040 is classified under CWE-288: Authentication Bypass Using an Alternate Path or Channel (The product requires authentication, but the product has an alternate path or channel that does not require authentication.).
How can I check Go dependencies for CVE-2026-34040?
Run the dependency tree command: 'inspect dependencies for github.com/moby/moby'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-x744-4wpc-v9h2",
  "modified" : "2026-08-24T16:43:38Z",
  "published" : "2026-03-27T17:43:16Z",
  "aliases" : [ "CVE-2026-34040" ],
  "summary" : "Moby has AuthZ plugin bypass when provided oversized request bodies",
  "details" : "## Summary\n\nA security vulnerability has been detected that allows attackers to bypass [authorization plugins (AuthZ)](https://docs.docker.com/engine/extend/plugins_authorization/) under specific circumstances. The base likelihood of this being exploited is low.\n\nThis is an incomplete fix for [CVE-2024-41110](https://github.com/moby/moby/security/advisories/GHSA-v23v-6jw2-98fq).\n\n## Impact\n\n**If you don't use AuthZ plugins, you are not affected.**\n\nUsing a specially-crafted API request, an attacker could make the Docker daemon forward the request to an authorization plugin without the body. The authorization plugin may allow a request which it would have otherwise denied if the body had been forwarded to it.\n\nAnyone who depends on authorization plugins that introspect the request body to make access control decisions is potentially impacted.\n\n## Workarounds\n\nIf unable to update immediately:\n- Avoid using AuthZ plugins that rely on request body inspection for security decisions.\n- Restrict access to the Docker API to trusted parties, following the principle of least privilege.\n\n## Credits\n\n- 1seal / Oleh Konko ([@1seal](https://github.com/1seal))\n- Cody (c@wormhole.guru)\n- Asim Viladi Oglu Manizada (@manizada)\n\n## Resources\n\n- [CVE-2024-41110 / GHSA-v23v-6jw2-98fq](https://github.com/moby/moby/security/advisories/GHSA-v23v-6jw2-98fq)",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/moby/moby"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "29.3.1"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/moby/moby/v2"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.0.0-beta.8"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/moby/moby/security/advisories/GHSA-v23v-6jw2-98fq"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/moby/moby/security/advisories/GHSA-x744-4wpc-v9h2"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-34040"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/moby/moby/commit/e89edb19ad7de0407a5d31e3111cb01aa10b5a38"
  }, {
    "type" : "WEB",
    "url" : "https://docs.docker.com/engine/extend/plugins_authorization"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/moby/moby"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/moby/moby/releases/tag/docker-v29.3.1"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-288", "CWE-863" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-27T17:43:16Z",
    "nvd_published_at" : "2026-03-31T03:15:57Z"
  }
}