CVE-2026-15792 Overview
CVE-2026-15792 is a denial of service vulnerability in the Moby BuildKit daemon. A malicious BuildKit client or frontend can craft a request that triggers a panic in the daemon, crashing the build service. The flaw is categorized under improper input validation [CWE-20] and impacts environments that expose BuildKit to untrusted build inputs or multi-tenant workloads. Because BuildKit underpins container image builds for many CI/CD pipelines and container platforms, a daemon crash can disrupt image production and downstream deployment workflows.
Critical Impact
A crafted client or frontend request can panic the BuildKit daemon, halting container image builds and interrupting CI/CD pipelines that depend on the service.
Affected Products
- Moby BuildKit (see GitHub Security Advisory GHSA-qx3x-mv6r-52p6 for affected versions)
- Container build systems and CI/CD platforms that embed BuildKit
- Development environments exposing BuildKit to untrusted frontends
Discovery Timeline
- 2026-07-21 - CVE-2026-15792 published to NVD
- 2026-07-21 - Last updated in NVD database
Technical Details for CVE-2026-15792
Vulnerability Analysis
CVE-2026-15792 is an input validation weakness in the BuildKit daemon's handling of client and frontend requests. BuildKit accepts build definitions and control messages from clients such as the Docker CLI, buildctl, and custom frontends. When one of these components submits a specifically crafted request, the daemon fails to validate the input correctly and reaches an unrecoverable state, resulting in a Go runtime panic that terminates the process.
The impact is availability-focused. The advisory indicates no impact on confidentiality or integrity, but the running daemon crashes and any in-flight builds are lost. Environments running BuildKit as a shared service, such as Kubernetes-based build clusters or remote BuildKit endpoints exposed to multiple teams, face repeated outages if an attacker can reach the daemon endpoint. The vulnerability requires low privileges (a valid client connection) and does not require user interaction.
Root Cause
The root cause is improper input validation [CWE-20] in the request-handling path of the BuildKit daemon. Malformed fields or unexpected values in a client or frontend request are not sanitized before use, allowing execution to reach a code path that panics. The maintainers describe the fix in the associated advisory.
Attack Vector
Exploitation requires network reachability to the BuildKit daemon and the ability to submit a build request as a client or frontend. An attacker with access to a shared BuildKit endpoint, or a malicious frontend loaded into a build pipeline, submits the crafted request and forces the daemon to panic. No memory corruption, code execution, or data exposure has been reported. Refer to the GitHub Security Advisory for technical details on the request structure.
Detection Methods for CVE-2026-15792
Indicators of Compromise
- Unexpected termination of the buildkitd process accompanied by a Go panic stack trace in daemon logs.
- CI/CD job failures with connection reset or gRPC unavailable errors against the BuildKit endpoint.
- Repeated daemon restarts within short intervals on shared build infrastructure.
Detection Strategies
- Monitor buildkitd service health and exit codes through the host init system (systemd, Kubernetes liveness probes).
- Parse daemon logs for panic: entries and Go runtime stack traces originating from request-handling functions.
- Correlate client source addresses with daemon crash timestamps to identify the originating request.
Monitoring Recommendations
- Alert on abnormal restart counts for BuildKit pods or containers within a rolling window.
- Track gRPC error rates and failed build sessions per client identity.
- Retain daemon logs and process telemetry in a central log store to support post-crash forensics.
How to Mitigate CVE-2026-15792
Immediate Actions Required
- Upgrade BuildKit to the patched version identified in GHSA-qx3x-mv6r-52p6.
- Restrict network access to the BuildKit daemon so that only trusted CI/CD systems and users can submit requests.
- Audit the list of frontends and client tools permitted to interact with shared BuildKit instances.
Patch Information
Refer to the Moby BuildKit GitHub Security Advisory for fixed release versions and upgrade guidance. Apply the patched release to all BuildKit daemons, including those embedded in container build platforms and CI runners.
Workarounds
- Isolate BuildKit daemons per tenant or per pipeline to limit blast radius from a crash.
- Enforce authentication and mutual TLS on BuildKit endpoints so only authorized clients can submit requests.
- Configure automatic restart policies for buildkitd to reduce downtime while patches are rolled out.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
