Bitwarden CLI npm Package Compromised in Supply Chain Attack

The Bitwarden CLI was briefly compromised after attackers uploaded a malicious package to npm containing a credential-stealing payload capable of spreading to other projects. According to reports by Socket, JFrog, and OX Security, the malicious package was distributed as version 2026.4.0 and remained available between 5:57 PM and 7:30 PM ET on April 22, 2026, before being removed. Bitwarden confirmed the incident, stating that the breach affected only its npm distribution channel for the CLI npm package and only those who downloaded the malicious version. "The investigation found no evidence that end user vault data was accessed or at risk, or that production data or production systems were compromised," Bitwarden said in a statement. "Once the issue was detected, compromised access was revoked, the malicious npm release was deprecated, and remediation steps were initiated immediately." According to Socket, threat actors appear to have used a compromised GitHub Action in Bitwarden's CI/CD pipeline to inject malicious code into the CLI npm package. JFrog reported that the package was modified so that the preinstall script and the CLI entry point use a custom loader named bw_setup.js, which checks for the Bun runtime and, if it does not exist, downloads it. The loader then uses the Bun runtime to launch an obfuscated JavaScript file named bw1.js, which acts as credential-stealing malware. Once executed, the malware collects a wide range of secrets from infected systems, including npm tokens, GitHub authentication tokens, SSH keys, and cloud credentials for AWS, Azure, and Google Cloud. The malware encrypts the collected data using AES-256-GCM and exfiltrates it by creating public GitHub repositories under the victim's account. OX Security reported that the malware features self-propagation capabilities and can use stolen npm credentials to identify packages the victim can modify and inject them with malicious code. Bitwarden told BleepingComputer the incident was linked to the Checkmarx supply chain attack, with a compromised Checkmarx-related development tool enabling abuse of the npm delivery path. Both campaigns have been linked to a threat actor known as TeamPCP.