A critical Docker Hub flaw allowed attackers to impersonate other users and potentially download, publish, or delete container images. Docker has fixed the vulnerability, tracked as CVE-2026-105445, and says its investigation found no evidence of exploitation.
The issue involved personal access tokens transferred during account conversions. Because attackers could retain a working token linked to another user, the vulnerability posed a software supply chain risk.
Account Conversions Exposed User Repositories
Docker Hub stores and distributes container images, which bundle applications with the components they need to run. Developers and automated workflows use personal access tokens, or PATs, to authenticate operations such as downloading and publishing images.
The vulnerability affected the process for converting a personal account into an organization. An attacker could create an account, generate a PAT, and then convert that account while naming another user as the organization owner.
During conversion, Docker Hub reassigned the existing token to the designated owner. However, it neither changed the token’s secret nor required that person to approve the transfer.
Consequently, the attacker retained a token that authenticated as the target user at the container registry level.
Image Tampering Created a Supply Chain Risk
The attacker’s capabilities depended on both the token’s scope and the target user’s permissions. Within those limits, the token could allow downloading, uploading, or deleting images in repositories the target could access.
That access could also extend to repositories belonging to organizations where the target held permissions.
Crucially, an attacker could potentially publish a modified image under a legitimate repository name. Downstream users might then download that image through an otherwise trusted distribution channel. Docker therefore classified the vulnerability as critical.
However, the Docker Hub flaw did not grant access to the service’s web interface. It also did not allow attackers to change passwords, email addresses, or two-factor authentication settings.
Docker Patched the Issue Within Four Hours
The vulnerability originated in a change introduced on August 26, 2024. From that point, account conversions reassigned existing PATs without revoking or rotating their secrets or obtaining the new owner’s confirmation.
Docker received a vulnerability report on September 30, 2026. The company confirmed the issue and deployed a production fix less than four hours later.
As part of its investigation, Docker examined 304,000 image pushes authenticated with transferred tokens. It also analyzed high-risk public images. According to the company, these checks uncovered no evidence of exploitation.
Transferred Tokens Deactivated After Notifications
Docker notified affected users and organization owners on October 2. It subsequently deactivated transferred PATs on October 8, except where owners explicitly requested to keep them.
According to Docker, users who received no notification should consider themselves unaffected and do not need to take action.
The platform has also changed its conversion process. It no longer transfers personal access tokens and now requires consent before assigning a user as an organization owner.
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