Cybersecurity researchers have disclosed particulars of a now-patched privilege escalation vulnerability in Google Cloud Platform (GCP) Cloud Run that might have allowed a malicious actor to entry container pictures and even inject malicious code.
“The vulnerability may have allowed such an identification to abuse its Google Cloud Run revision edit permissions with a view to pull personal Google Artifact Registry and Google Container Registry pictures in the identical account,” Tenable safety researcher Liv Matan mentioned in a report shared with The Hacker Information.
The safety shortcoming has been codenamed ImageRunner by the cybersecurity firm. Following accountable disclosure, Google addressed the issue as of January 28, 2025.
Google Cloud Run is a completely managed service for executing containerized purposes in a scalable, serverless atmosphere. When the expertise is used to run a service, container pictures are retrieved from the Artifact Registry (or Docker Hub) for subsequent deployment by specifying the picture URL.
At challenge is the truth that there are particular identities that lack container registry permissions however which have edit permissions on Google Cloud Run revisions.
Every time a Cloud Run service is deployed or up to date, a brand new model is created. And every time a Cloud Run revision is deployed, a service agent account is used to drag the mandatory pictures.
“If an attacker features sure permissions inside a sufferer’s venture — particularly run.companies.replace and iam.serviceAccounts.actAs permissions — they may modify a Cloud Run service and deploy a brand new revision,” Matan defined. “In doing so, they may specify any personal container picture throughout the similar venture for the service to drag.”
What’s extra, the attacker may entry delicate or proprietary pictures saved in a sufferer’s registries and even introduce malicious directions that, when executed, could possibly be abused to extract secrets and techniques, exfiltrate delicate knowledge, and even open a reverse shell to a machine underneath their management.
The patch launched by Google now ensures that the person or service account creating or updating a Cloud Run useful resource has express permission to entry the container pictures.
“The principal (person or service account) creating or updating a Cloud Run useful resource now wants express permission to entry the container picture(s),” the tech large mentioned in its launch notes for Cloud Run in January 2025.
“When utilizing Artifact Registry, make sure the principal has the Artifact Registry Reader (roles/artifactregistry.reader) IAM function on the venture or repository containing the container picture(s) to deploy.”
Tenable has characterised ImageRunner for instance of what it calls Jenga, which arises as a result of interconnected nature of assorted cloud companies, inflicting safety dangers to be handed alongside.
“Cloud suppliers construct their companies on high of their different present companies,” Matan mentioned. “If one service will get attacked or is compromised, the opposite ones constructed on high of it inherit the danger and grow to be weak as effectively.”
“This state of affairs opens the door for attackers to find novel privilege escalation alternatives and even vulnerabilities, and introduces new hidden dangers for defenders.”
The disclosure comes weeks after Praetorian detailed a number of methods a lower-privilege principal can abuse an Azure digital machine (VM) to achieve management over an Azure subscription –
- Execute instructions on an Azure VM related to an administrative managed identification
- Log in to an Azure VM related to an administrative managed identification
- Connect an present administrative user-assigned managed identification to an present Azure VM and execute instructions in that VM
- Create a brand new Azure VM, connect an present administrative managed identification to it, and execute instructions in that VM through the use of knowledge airplane actions
“After acquiring the Proprietor function for a subscription, an attacker might be able to leverage their broad management over all subscription sources to discover a privilege escalation path to the Entra ID tenant,” safety researchers Andrew Chang and Elgin Lee mentioned.
“This path is based on a compute useful resource within the sufferer subscription with a service principal with Entra ID permissions which will permit it to escalate itself to World Administrator.”
