AWS Deadline Cloud flaw let a job run code as the worker agent

AWS Deadline Cloud flaw let a job run code as the worker agent

10 November 2026: AWS has fixed CVE-2026-126087, an untrusted-search-path flaw in OpenJD Sessions for Python and the AWS Deadline Cloud worker agent that let a user who can submit jobs run arbitrary code as the worker agent's operating-system user on Linux. Customer-managed fleets need openjd-sessions 0.11.0 and deadline-cloud-worker-agent 0.33.0. AWS rates bulletin 2026-177-AWS as Important (requires attention), gives no CVSS score and reports no exploitation.

How the sudo lookup went wrong

AWS Deadline Cloud is a managed service for rendering and other compute-heavy workloads. Its worker agent runs on fleet hosts and uses the open-source Open Job Description (OpenJD) Sessions library to run each job's actions as the queue's job user.

On Linux, the library switched to the job user by running sudo by its bare name, in an environment that the job controls. A job could add a directory to PATH and put its own executable called sudo there. That executable would run as the worker agent user instead of the job user.

What an attacker could reach

The attacker needs to be authenticated and to hold permission to submit jobs to a queue. From the worker agent user, AWS says they could obtain the AWS credentials it holds, including fleet role credentials and EC2 instance identity credentials. On customer-managed fleets they could also read or modify other queues' session data and queue role credentials on the same host.

Versions and the fix

• openjd-sessions: affected before 0.11.0, fixed in 0.11.0.
• deadline-cloud-worker-agent: affected before 0.33.0, fixed in 0.33.0, which includes OpenJD Sessions 0.11.0.

The new code finds sudo and its other system commands in a fixed list of trusted directories and never looks them up through PATH. AWS recommends upgrading to the latest worker agent and checking that forked or derivative code includes the fix.

Who has to act

Service-managed fleets were remediated service-side, and AWS says those customers need take no action. Customer-managed fleets running an affected worker agent on Linux are affected. Windows workers are not.

Reducing exposure until the upgrade

AWS says upgrading is the only fix and that no configuration setting removes the issue. Until a customer-managed fleet is upgraded, AWS advises limiting the deadline:CreateJob permission on its queues to trusted principals.

Customers who ran affected versions on customer-managed fleets should review AWS CloudTrail for unexpected activity by their fleet role and queue roles, since stolen role credentials would be used through those identities. The bulletin also references the GitHub advisory GHSA-g25v-j45m-7425 for the open-source library.

Sources

• AWS Security Bulletin 2026-177-AWS: CVE-2026-126087, Untrusted search path in OpenJD Sessions for Python and the AWS Deadline Cloud worker agent, 10 November 2026, 10 November 2026