CVE-2026-50151 in oras-go
Summary
by MITRE • 07/17/2026
oras-go is a Go library for managing OCI artifacts. Prior to 2.6.1, registry/remote/repository.go in blobStore.completePushAfterInitialPost follows a registry-controlled Location header during monolithic blob upload and reuses the Authorization header from the initial POST request for the subsequent PUT request, allowing a malicious registry to return a cross-host Location and receive the caller's credentials at an attacker-controlled endpoint. This issue is fixed in version 2.6.1.
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Analysis
by VulDB Data Team • 07/17/2026
The oras-go library serves as a critical component for managing Open Container Initiative artifacts in Go applications, facilitating secure container image operations across various registries. A significant security vulnerability existed in versions prior to 2.6.1 where the blobStore.completePushAfterInitialPost function demonstrated a dangerous pattern of credential handling during monolithic blob uploads. The flaw occurs when the library processes registry responses containing Location headers that direct subsequent operations to different hosts. This behavior creates an avenue for malicious registry servers to manipulate the client's authentication flow by returning cross-host Location headers that point to attacker-controlled endpoints.
The technical implementation of this vulnerability stems from the library's failure to validate or sanitize the Location header values returned by the registry server. During the blob upload process, after an initial POST request establishes the upload session, the system expects a Location header in the response containing the URI for the subsequent PUT operation. However, the oras-go library indiscriminately accepts this Location header value and reuses the original Authorization header from the initial POST request when making the follow-up PUT request. This design pattern directly violates security best practices for credential handling and authentication delegation.
The operational impact of this vulnerability extends beyond simple credential theft, creating potential attack vectors that align with several ATT&CK techniques including T1566 for credential access through malicious registry manipulation and T1071 for application layer protocol usage. Attackers can leverage this flaw by hosting malicious registry servers that return carefully crafted Location headers pointing to their own endpoints. When legitimate clients attempt to complete blob uploads, they inadvertently send their authorization credentials to these attacker-controlled servers, potentially compromising authentication tokens, API keys, or other sensitive authentication material. This creates a persistent threat where attackers can harvest credentials for multiple systems that rely on the oras-go library for registry operations.
The vulnerability manifests specifically in the registry/remote/repository.go file within the blobStore.completePushAfterInitialPost function, which implements the monolithic blob upload strategy. This pattern typically occurs during large artifact uploads where the registry provides a Location header to guide the client through a multi-step upload process. The CWE classification for this issue relates to CWE-200 Information Exposure and potentially CWE-352 Cross-Site Request Forgery, as the vulnerability enables unauthorized access to authentication credentials through manipulated registry responses. Organizations using oras-go in their container orchestration, CI/CD pipelines, or artifact management systems face significant risk of credential compromise when running vulnerable versions.
The fix implemented in version 2.6.1 addresses this issue by introducing proper validation and sanitization of Location header values before proceeding with subsequent requests. This mitigation ensures that the library only accepts Location headers that maintain the same host context as the original request, preventing cross-host credential delegation to attacker-controlled endpoints. The updated implementation aligns with security standards for authentication handling and prevents the unauthorized reuse of credentials across different host domains. System administrators should prioritize upgrading to version 2.6.1 or later to eliminate this exposure, particularly in environments where container images are managed through registries that may not be fully trusted or where automated deployment processes rely on oras-go for artifact operations.