Docker Hub Token Reassignment Flaw Enabled Registry Impersonation
A critical flaw in Docker Hub allowed attackers to hijack personal access tokens during account conversions, posing supply chain risks until a patch was deployed.
Key points
- CVE-2026-105445 allowed authenticated attackers to reassign personal access tokens to target users without rotating secrets.
- The vulnerability existed from August 26, 2024, until Docker deployed a fix on September 30, 2026.
- Docker found no evidence of exploitation after analyzing hundreds of thousands of image pushes.
Docker Hub suffered a critical security failure that allowed attackers to impersonate other users at the registry level. The flaw, tracked as CVE-2026-105445, stemmed from how the platform handled personal access tokens during the conversion of personal accounts into organizations. Attackers could create an account, generate a token, and then convert that account into an organization while naming a victim as the owner. This action reassigned the token to the victim without changing its secret or obtaining consent, allowing the attacker to authenticate as the target user.
The risk
The vulnerability received a CVSS score of 9.4, rated as critical by the National Vulnerability Database. It was classified as an incorrect privilege assignment weakness, specifically CWE-266. Because the token secret remained unchanged, the attacker retained access while the registry associated the credential with the victim’s identity. Within the token’s defined scopes, the attacker could pull, push, or delete container images in repositories accessible to the victim, including those within organizations where the victim held permissions.
Who is exposed
The exposure window lasted from August 26, 2024, at 20:33 UTC, until the fix was deployed on September 30, 2026, at approximately 19:10 UTC. Any user whose account was targeted during this period could have had their access tokens hijacked. The flaw did not grant access to the Docker Hub web interface, meaning attackers could not change passwords, email addresses, or two-factor authentication settings. However, the ability to publish images under legitimate names created a software supply chain risk for downstream users relying on those repositories.
Cost and compliance
Docker stated that it treated the issue as a software supply chain risk due to the potential for publishing malicious code under trusted names. The company investigated 304,000 pushes made with transferred tokens and analyzed high-risk public images but found no evidence of exploitation. Affected users and organization owners were notified on October 2, and transferred personal access tokens were deactivated on October 8, except for those whose owners explicitly requested to retain them.
What to watch
Security teams should verify that no legacy tokens remain active from the period between August 2024 and September 2026. Organizations should review repository access logs for unusual push or delete activities originating from unexpected sources. Monitoring for new organization conversions involving known user accounts can help detect similar credential handling anomalies in the future.
Signals worth monitoring
Teams usually detect this type of impersonation by analyzing registry logs for token usage patterns that deviate from established baselines. Check whether authentication events show a single token secret being used from disparate geographic locations or IP ranges within a short timeframe. Look for image pushes to repositories that the token owner typically does not modify. Containment moves involve immediately rotating all active personal access tokens and revoking any that were generated during the vulnerability window. Audit organization ownership changes to ensure no unauthorized transfers occurred.
Background: Supply chain attacks
Protect your organization by verifying software signatures, isolating third-party access, and monitoring dependencies. This checklist provides specific actions to reduce risk from compromised vendors, ensuring your security posture remains intact even when external partners fail.
Read the full guide: Supply Chain Attack Prevention Checklist for Secure Operations
What to do and how to stay safe: Docker Hub
- Rotate all personal access tokens that were active during the exposure window to ensure no hijacked credentials remain valid.
- Review registry audit logs for unexpected image pushes or deletions from accounts that do not typically perform those actions.
- Verify that organization ownership conversions were authorized and that no unknown users were designated as owners during the risk period.
- Enable enhanced logging for registry authentication events to detect future anomalies in token usage patterns.
Step-by-step guide: Vulnerability Prioritization: Fix What Actually Matters First
General security guidance from the SecOps Signal newsroom. It is not confirmed advice from the organisations named in this story.
Frequently asked questions
Did attackers exploit this Docker Hub vulnerability?
Docker found no evidence of exploitation after analyzing 304,000 pushes made with transferred tokens.
Could attackers take over full Docker Hub accounts using this flaw?
No, the flaw did not allow access to the web interface or changes to passwords and two-factor authentication settings.
When was the fix for CVE-2026-105445 deployed?
Docker deployed a fix to production on September 30, 2026, less than four hours after receiving the report.
