# Grafana Breach Exposes Critical Weakness in Supply Chain Incident Response: How One Missed Token Led to Codebase Theft
A GitHub workflow token overlooked during emergency rotation gave attackers sustained access to Grafana's repositories, revealing dangerous gaps in crisis recovery procedures.
## The Incident
Grafana Labs disclosed on May 20, 2026 that attackers gained access to its private GitHub repositories following a supply chain attack on the TanStack npm packages. The breach stemmed from a single GitHub workflow token that slipped through the company's token rotation process in early May—a seemingly routine credential management task that became a critical vulnerability in the wake of a larger incident.
The attackers, attributed to the TeamPCP hacking collective, used the forgotten token to steal Grafana's source code, business operational information, and contact details belonging to professional relationships. While Grafana confirmed that no customer production data was compromised and the codebase itself remains unmodified, the incident underscores a sobering reality: even security-conscious organizations can fail at the fundamentals when managing crisis response at scale.
## Background and Context: The TanStack Supply Chain Attack
To understand Grafana's breach, the timeline of events matters enormously.
On May 1, 2026, Grafana detected malicious activity originating from compromised TanStack packages on the npm repository. TeamPCP had orchestrated what researchers are calling the Shai-Hulud malware campaign—a sophisticated supply chain attack that infected dozens of TanStack packages with credential-stealing malware.
TanStack is a popular JavaScript ecosystem used by developers globally. The packages—which include widely-used libraries—were poisoned with an info-stealer module designed to exfiltrate sensitive credentials from developer environments. When Grafana's continuous integration (CI/CD) pipeline pulled the malicious dependencies, the malware executed within Grafana's GitHub Actions environment.
The attack was particularly insidious because it exploited a trust relationship: developers depend on npm packages to be legitimate, and automated CI/CD systems routinely fetch and execute those dependencies. Grafana, like thousands of other organizations, had no immediate way to distinguish the poisoned packages from legitimate releases.
## Technical Details: How the Attack Unfolded
The infection vector was direct and efficient:
1. Poisoned packages published: TeamPCP released modified versions of TanStack libraries to npm, embedding credential-stealing code.
2. Automated consumption: Grafana's CI/CD workflows pulled the packages as part of normal build processes.
3. Malware execution: The info-stealer module ran within GitHub Actions, with full access to Grafana's GitHub environment variables and secrets.
4. Token exfiltration: GitHub workflow tokens—used for authenticating to Grafana's private repositories—were stolen and sent to attacker-controlled servers.
The missed token reveals the crisis response gap. When Grafana detected the malicious activity and initiated incident response procedures, teams rotated what they believed to be all compromised GitHub workflow tokens. However, a specific workflow token associated with a repository they initially deemed "not impacted" was overlooked.
This misclassification proved fatal to containment. Using the forgotten token, attackers maintained persistent access to Grafana's GitHub repositories, eventually downloading:
## The Human Error Factor: Rotation at Scale
The Grafana incident exemplifies a critical failure mode in incident response: complexity breeding incompleteness.
During a major supply chain incident, security teams must:
When multiple workflows, services, and teams are involved, this process becomes a coordination nightmare. One workflow misclassified as "not impacted" is enough. One developer forgetting to rotate a key. One shared credential not updated in time.
Grafana's incident response was not negligent—the company mobilized quickly and rotated a "significant number" of tokens. But in the rush to contain the immediate threat, one token fell through the cracks. A subsequent review finally identified the compromised workflow, but only after the attackers had already accessed the repositories.
This pattern repeats across breach after breach: the first response is often incomplete, and the attack persists until the second or third review identifies what was initially missed.
## Scope of the Breach: What Was and Wasn't Compromised
| Category | Compromised? | Details |
|----------|--------------|---------|
| Customer production data | No | Explicitly confirmed unaffected |
| Customer systems | No | No evidence of compromise |
| Grafana source code | Yes | Entire codebases downloaded |
| Operational information | Yes | Business processes, internal details |
| Professional contact data | Yes | Names, emails from business relationships |
| Code integrity | Intact | Codebase was not modified |
| Grafana Cloud platform | No | Production systems confirmed unaffected |
Grafana was clear on one critical point: users do not need to take action. The codebase remained unmodified, meaning no backdoors were inserted and no malicious code was distributed to customers. The attackers exfiltrated intellectual property and operational information, but did not weaponize the stolen source code—at least not yet.
## Implications for Organizations
This incident carries lessons far beyond Grafana:
Supply chain attacks require dual-layer response. Organizations cannot simply patch the immediate vulnerability and declare victory. When malware executes in your build environment with access to secrets, assume all tokens and credentials in that environment are compromised. Rotate everything that could have been accessed, then rotate it again.
Token rotation must be inventory-driven, not memory-driven. Teams that manually track which tokens exist across CI/CD systems will inevitably miss one. Automated inventory and rotation—where a script identifies all tokens, rotates them systematically, and logs the process—are essential.
Crisis response handoffs are dangerous. When incident response is divided across teams, tokens or workflows can fall into the cracks between departments. Centralized logging and explicit verification by a different team than the one that performed the initial rotation catches these gaps.
Ransomware is secondary to exfiltration. Grafana received extortion demands from the attackers and refused to pay. The attackers proceeded anyway—likely planning to monetize the stolen source code and operational data through other channels (TeamPCP has been observed selling stolen code repositories to other threat actors).
## Recommendations for Defenders
Immediate actions for organizations using TanStack or similar widely-distributed npm packages:
Long-term structural improvements:
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## HackWire Analysis
The real vulnerability here is organizational process, not code.
Grafana's incident response was reasonably fast—they detected the malicious activity on May 1 and rotated tokens within a compressed timeline. But "reasonably fast" in a crisis of this magnitude creates the exact conditions for missed steps. Security teams operating under pressure, managing dozens of parallel tasks, and coordinating across multiple departments will cut corners and overlook details.
The missed token is emblematic of a broader trend: supply chain attacks are now sophisticated enough to exploit human fallibility in the response phase itself. TeamPCP didn't need to modify Grafana's code or maintain persistence through backdoors. They just needed to wait for Grafana's team to finish rotating credentials, identify the one mistake in the process, and continue operating with stolen access.
This incident also reveals that source code theft is now treated as a business outcome, not a catastrophe. Grafana downplayed the breach because (1) no customer data was stolen and (2) the code wasn't modified. But stolen intellectual property is valuable to competitors, regulators, and other threat actors. TeamPCP is already advertising Mistral AI code repositories for sale on underground forums. The Grafana source code will likely follow the same path.
The incident validates a hard lesson for defenders: in supply chain compromises, assume total credential loss in affected environments. Rotate tokens you know were accessed, then rotate everything that *could have been* accessed. Build redundancy into your incident response so that one team member's oversight doesn't become an attacker's persistence mechanism.
Organizations should also revisit how they treat source code theft. If your codebase is worth protecting, it's worth protecting even when no customer data is at stake.
— HackWire Editorial
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