GitHub reviewed security changes implemented over recent months in npm and GitHub Actions to disrupt common techniques in software supply chain attacks and limit their impact. The measures include protecting high-impact npm accounts, tightening the default behavior of Actions workflows, reducing the risk of credential theft, and providing faster tools for incident response.
These steps followed an increase in attacks exploiting weaknesses in package repositories and continuous integration and deployment systems to distribute malware to hundreds of open-source projects. According to Greg Ose and Zachary Steindler, these attacks typically follow a series of stages that begin with initial access to a project, followed by privilege escalation and credential theft, and ultimately spread to other projects and users.
Reducing Opportunities for Initial Compromise
In June 2026, npm placed high-impact accounts in read-only mode for 72 hours when the email address was changed or a token was used to recover two-factor authentication. This window gives account administrators time to detect and respond to phishing attempts before the account is used to launch an attack.
That same month, GitHub changed the default behavior of the actions/checkout action to prevent untrusted code from being fetched from pull requests originating in forked repositories for commonly exploited triggers, with the option to override the restriction after reviewing the risks. The change also covered older versions of the action.
GitHub also made organization-, enterprise-, and repository-level policies available to control which entities are allowed to run workflows and which types of triggers are accepted. In addition, it restricted the ability of less-trusted workflows to modify the cache shared with other workflows, cutting off a path that had been used to move from limited-permission execution to the theft of highly privileged credentials.
Limiting Credential Theft and Malware Propagation
In April 2026, npm added CircleCI support to its trusted publishing feature, allowing projects to publish through a trusted entity instead of using long-lived credentials that attackers can extract from continuous integration environments.
GitHub is also testing a network firewall in technical preview that logs outbound traffic from GitHub Actions jobs. This helps detect behavior such as downloading malicious code or sending credentials to new domains. GitHub plans to later add restrictions and policies for outbound network traffic to prevent these activities.
With the staged publishing feature launched by npm in May 2026, credentials alone are not sufficient to publish a new release immediately; the release remains pending until it is approved and two-factor authentication is completed through the npm interface or npmjs.com.
npm v12 is also preparing a breaking change that will disable lifecycle scripts during installation by default, while allowing specific scripts to be re-enabled after approval. Dependencies that rely on Git repositories or remote URLs will also be disabled by default, limiting code execution paths during installation.
Delaying Non-Security Updates and Improving Response
Starting in July 2026, version updates through Dependabot began waiting at least three days after a package was released before opening a pull request. This gives detection signals time to emerge before a malicious release reaches projects, while security updates continue to open immediately so that critical fixes are not delayed.
On the response side, GitHub added self-service tools in June to revoke all credentials for a specific user within an organization. In March, it also expanded support for its credential-revocation API to include GitHub OAuth tokens and App Tokens, after support for personal access tokens was introduced in April 2025. GitHub says these capabilities help quickly invalidate leaked credentials and reduce the period during which they can be misused.
GitHub confirmed that these changes are part of ongoing work to make npm and GitHub Actions more secure by default, with additional improvements continuing to roll out and being tracked through the changelog and blog posts.