Unit 42: Threat Assessment: GitHub Actions Supply Chain Attack: The Compromise of tj-actions/changed-files

Mar 18, 2025

—

Source URL: https://unit42.paloaltonetworks.com/github-actions-supply-chain-attack/
Source: Unit 42
Title: Threat Assessment: GitHub Actions Supply Chain Attack: The Compromise of tj-actions/changed-files

Feedly Summary: A compromise of the GitHub action tj-actions/changed-files highlights how attackers could exploit vulnerabilities in third-party actions to compromise supply chains.
The post Threat Assessment: GitHub Actions Supply Chain Attack: The Compromise of tj-actions/changed-files appeared first on Unit 42.

AI Summary and Description: Yes

Summary: The text discusses a substantial security incident involving the compromise of a GitHub Action that poses risks to CI/CD pipelines and software supply chains. It highlights how third-party dependencies can be exploited, leading to unauthorized access and breaches, thereby underscoring the need for stringent security measures.

Detailed Description:
This analysis revolves around the recent compromise of the GitHub Action tj-actions/changed-files and its implications for software security in CI/CD pipelines. The key points discussed are:

– **Incident Overview**:
– The tj-actions/changed-files action was compromised, which is utilized by over 23,000 repositories, exposing sensitive workflow secrets.
– The attack was detected on March 14, 2025, when security researchers noted suspicious activity linked with the action, suggesting a significant vulnerability in the software supply chain.

– **Attack Methodology**:
– The attackers exploited unauthorized modifications to tagged releases, directing these to a compromised commit equipped with a malicious payload.
– A GitHub Personal Access Token (PAT) linked to an automated bot account facilitated the attack, emphasizing the need for better security controls like signed commits and branch protection rules.

– **Consequences of the Attack**:
– The malicious payload extracted and printed sensitive information in workflow logs, which are publicly accessible and could lead to severe data breaches.
– The incident indicates a broader vulnerability within CI/CD environments by exposing that multiple actions related to the reviewdog organization were also compromised.

– **Mitigation Strategies**:
– Immediate actions for affected users include identifying the usage of the compromised actions, reviewing logs for exposed secrets, rotating credentials, and investigating for malicious activities.
– Long-term improvements suggested include implementing stricter governance on third-party services, fine-grained access controls (PBAC), and pinning dependencies to specific commit hashes.

– **Security Implications**:
– The ability of the compromised action to access workflow secrets highlights the need for robust security practices in GitHub Actions workflows, particularly concerning permission settings for generated tokens.

– **Recommendations from Palo Alto Networks**:
– Palo Alto Networks emphasizes the deployment of their Prisma Cloud and Cortex Cloud products to enhance CI/CD security and offer out-of-the-box policies to identify vulnerabilities effectively.

Key Long-Term Recommendations Include:
– Pinning dependencies to specific code versions.
– Restricting allowed actions within repositories.
– Using OpenID Connect (OIDC) to manage short-lived credentials rather than long-term ones.

This incident serves as a potent reminder of the vulnerabilities inherent in relying on third-party components within critical software deployment processes and the imperative for organizations to adopt a proactive security-first approach to combat potential threats in their CI/CD pipelines.

1 2 2025 3 4 5 a access access control access controls access token account Act actions AI alt analysis and anti Arch art as assessment attack attack method attack methodology attackers Auto breach breaches by C C code CERN chain chain attack CI/CD Cloud Cloud Products co code compromised control controls Cortex credential credentials critical D data data breach Data breaches de dependencies deployment deployment processes e effective end environment exp exploit fine first Flow Logs for g Gen generated git GitHub GitHub Action GitHub Actions Go governance gs H high Highlight HR http HTTPS implications in incident information IRS ite J k Key l led Li Link linked logs long low malicious activities malicious payload man media mission mitigation mitigation strategies ModI multi N network networks no o of off on one open opt organization organizations out over Palo Alto Palo Alto Networks party party actions party components party dependencies permission settings Pipeline pipelines point policies post potential Prisma proactive proactive security process processes product products protection public R rate RCE recommendations red release releases research researchers Risk risks Ro robust security robust security practices RoT s search sec secrets security security controls security implications security incident security measure security measures security practices Security Research Security Researcher security researchers sensitive information sequence service services settings short Sig software software deployment software security software supply chain source specific SSE STIG supply supply chain supply chain attack supply chains T text the third third-party third-party actions threat threat assessment threats to token tokens Tor TP two UI unauthorized access Unit 42 up US usage use user Users uth V version vulnerabilities vulnerability Ware Wi workflow workflow logs workflows x