Backstage vulnerabilities, page 3
72 vulnerabilities
Known vulnerabilities in Backstage products, newest first, with CVSS severity, EPSS, KEV listings and ransomware use, across 28 products.
CVE-2026-106456backstagebackstage+2
EPSS score0.24%
Backstage is an open framework for building developer portals. From 0.5.0 until 0.6.18, the @backstage/plugin-proxy-backend package is affected by inconsistent credential enforcement for overlapping proxy routes. An operator can configure overlapping proxy paths with different credential requirements. When a parent path permits unauthenticated access and a nested path requires credentials, the parent exemption can also cover requests handled by the nested proxy. An unauthenticated caller may therefore reach the nested upstream through Backstage, including with static upstream credentials configured for that proxy. This issue is fixed in version 0.6.18.CVE-2026-106487backstagebackstage+2EPSS score0.26%
Backstage is an open framework for building developer portals. Prior to 0.21.10, the @backstage/plugin-kubernetes-backend package is affected by unsupported catalog cluster authentication mode in kubernetes backend. Deployments using catalog cluster discovery may be affected when catalog contributors can create or modify kubernetes-cluster Resource entities. With the required endpoint permissions and pod RBAC, the backend can use its local in-cluster identity, potentially exposing Kubernetes resources readable by that identity. The credential is used only with the local in-cluster API endpoint and is not sent to the catalog-supplied endpoint. This issue is fixed in version 0.21.10.CVE-2026-106492@backstagebackend-defaults+2EPSS score0.24%
Backstage is an open framework for building developer portals. Prior to 0.16.1 and 0.17.8, the @backstage/backend-defaults package is affected by improper preservation of access restrictions during service credential delegation. An external service credential configured with access restrictions (e.g., read-only) could bypass those restrictions by routing requests through plugin delegation paths. This could allow a restricted service to perform operations beyond its intended scope, including write operations on plugins it was restricted to read-only access for. This issue is fixed in versions 0.16.1 and 0.17.8.CVE-2026-106507backstagebackstage+3EPSS score0.31%
Backstage is an open framework for building developer portals. Prior to 1.15.4, the @backstage/plugin-techdocs-node package is affected by techdocs arbitrary file read via mkdocs snippets. Unsafe path resolution in TechDocs source tree handling allows an authenticated user who can register documentation sources to include content from outside the intended documentation boundary. Depending on deployment, this may expose files readable by the build process. This issue is fixed in version 1.15.4.CVE-2026-106504backstagebackstage+4EPSS score0.26%
Backstage is an open framework for building developer portals. Prior to 4.1.0, the @backstage/plugin-scaffolder-backend package is affected by sensitive information exposure in scaffolder task logs. An authenticated user who can create and read scaffolder tasks may be able to observe sensitive values in task logs in deployments with restrictive action permissions and affected templates. Exploitation requires a denied action whose input contains such a value. This issue is fixed in version 4.1.0.CVE-2026-106497backstagebackstage+3EPSS score0.19%
Backstage is an open framework for building developer portals. Prior to 3.9.1, the @backstage/plugin-catalog-backend package is affected by inconsistent catalog property permission evaluation. In deployments that use affected value-based catalog permission conditions as a confidentiality boundary, an authenticated user could receive catalog entity data that policy authors intended to restrict. This issue is fixed in version 3.9.1.CVE-2026-106494@backstagebackend-defaults+2EPSS score0.29%
Backstage is an open framework for building developer portals. Prior to 0.17.8, the @backstage/backend-defaults package is affected by improper input validation in cloud storage url readers. An attacker with write access to a cloud storage bucket used by Backstage could craft object names that could collide with protected files in the output directory. In certain deployment configurations, this could lead to content injection. This issue is fixed in version 0.17.8.CVE-2026-106501backstagebackstage+4EPSS score0.48%
Backstage is an open framework for building developer portals. Prior to 3.3.1, 3.4.1, 4.0.3 and 4.1.0, the @backstage/plugin-scaffolder-backend package is affected by sensitive information exposure in scaffolder. An authenticated Backstage user who can read another user's Scaffolder task may receive internal execution data. In deployments where that data contains credentials for an external service, this may permit disclosure and unauthorized changes in that external service. This issue is fixed in versions 3.3.1, 3.4.1, 4.0.3 and 4.1.0.CVE-2026-106460backstagebackstage+2EPSS score0.31%
Backstage is an open framework for building developer portals. From 0.3.0 until 0.6.15 and 0.7.5, the @backstage/plugin-auth-node package did not consistently honor explicit negative email verification during shared OAuth profile normalization. The affected paths include a selected profile email marked verified: false, a matching raw provider email marked email_verified: false, and an email obtained only from an ID token marked email_verified: false. Exploitation requires an admitted identity-provider user who can supply or change an unverified email and a deployment that uses the selected profile email to resolve catalog identities. The verification metadata must apply to the selected email; an absent email_verified claim alone is not affected. In an affected configuration, the user may assume another catalog identity and obtain its associated access and permissions. This issue is fixed in versions 0.6.15 and 0.7.5.CVE-2026-106496backstagebackstage+4EPSS score0.24%
Backstage is an open framework for building developer portals. Prior to 3.9.1, the @backstage/plugin-catalog-backend package is affected by inconsistent enforcement of allowed location types during catalog processing. Under certain configurations, the catalog backend could process location types that were not intended to be allowed, potentially leading to unintended file access on the backend host. This issue is fixed in version 3.9.1.CVE-2026-106488backstagebackstage+2EPSS score0.28%
Backstage is an open framework for building developer portals. Prior to 0.4.20, the @backstage/plugin-auth-backend-module-oidc-provider package is affected by improper authentication in the oidc provider. Deployments using OIDC email-based identity resolution with a provider that permits unverified email addresses may allow an authenticated provider user to assume another catalog identity. This may grant access and permissions associated with that user. No direct availability impact is demonstrated. This issue is fixed in version 0.4.20.CVE-2026-106462backstagebackstage+12EPSS score0.17%
Backstage is an open framework for building developer portals. Prior to 1.54.6, scaffolder source-control actions may not consistently enforce intended credential boundaries. An authenticated user could cause an affected action to fall back to broader integration credentials and perform operations with more access than intended. This issue is fixed in 1.54.6 when operators also enable scaffolder.requireScmUserCredentials after upgrading.CVE-2026-106561backstagebackstage+4EPSS score0.20%
Backstage is an open framework for building developer portals. Prior to 0.21.9, the @backstage/plugin-kubernetes-backend package is affected by sensitive information disclosure in kubernetes resource queries. An authenticated user holding the standard Kubernetes resource read permission could retrieve sensitive values that the Kubernetes plugin is designed to mask, potentially exposing credentials and other confidential material held in the connected clusters. Exposure is limited to resources that the Backstage service account is permitted to read and that match the targeted catalog entity's namespace and label selector. Deployments whose cluster credentials do not grant read access to these resources are unaffected. This issue is fixed in version 0.21.9.CVE-2026-106558backstagebackstage+4EPSS score0.47%
Backstage is an open framework for building developer portals. Prior to 1.14.8, 1.15.6, and 2.0.1, the @backstage/plugin-techdocs-node package improperly validated mapping-style markdown_extensions configuration. An authenticated attacker who can register or influence an SCM-backed documentation source may bypass TechDocs sanitization and cause Python objects to be imported and instantiated in the generator runtime, leading to arbitrary code execution. Earlier fixes in versions 1.14.6 and 1.15.4 did not fully address the supported mapping representation of markdown_extensions. Impact is greatest when documentation generation runs with backend credentials, filesystem access, or internal network access. This issue is fixed in versions 1.14.8, 1.15.6, and 2.0.1.CVE-2026-106458backstagebackstage+2EPSS score0.27%
Backstage is an open framework for building developer portals. From 0.4.0 until 0.5.15, the @backstage/plugin-catalog-backend-module-bitbucket-server package is affected by inconsistent repository filtering in bitbucket server catalog event updates. Deployments using event-driven updates in the Bitbucket Server catalog provider may ingest catalog locations from repositories that are excluded by the provider's configured project, repository, or archived-repository filters. An authenticated Bitbucket Server user who can push to a filtered-out repository that remains readable by the configured Backstage integration can trigger a legitimate repository event. The affected event path may then add a Location for that repository even though scheduled discovery excludes it. This issue is fixed in version 0.5.15.CVE-2026-106490backstagebackstage+2EPSS score0.36%
Backstage is an open framework for building developer portals. Prior to 2.2.4, the @backstage/plugin-techdocs-backend package is affected by improper input validation in techdocs static content requests. When using the Azure Blob Storage provider, an authenticated Backstage user may be able to read restricted TechDocs content when entity-level permissions are enabled. Deployments that intentionally disable the default backend authentication policy may have broader exposure. This issue is fixed in version 2.2.4.CVE-2026-106463backstagebackstage+2EPSS score0.17%
Backstage is an open framework for building developer portals. Prior to 0.8.7, the @backstage/plugin-catalog-backend-module-gitlab package is affected by improper authorization in gitlab organizational user ingestion. Deployments that enable GitLab organization event ingestion and rely on scoped catalog users as an access boundary may admit an unintended catalog identity. Depending on sign-in and permission configuration, this may allow unauthorized access with the permissions of a standard authenticated user. This issue is fixed in version 0.8.7.CVE-2026-106508backstagebackstage+4EPSS score0.31%
Backstage is an open framework for building developer portals. Prior to 1.15.4, the @backstage/plugin-techdocs-node package is affected by potential file exposure through local techdocs publisher. When using the local TechDocs publisher (techdocs.publisher.type: 'local'), it was possible for the documentation serving endpoint to follow filesystem references outside the intended documentation tree, potentially exposing host files to authenticated users. This is mitigated by the fact that exploration requires preconditions that do not arise through normal MkDocs operation. Cloud-based publishers (S3, GCS, Azure Blob Storage) are not affected. This issue is fixed in version 1.15.4.CVE-2026-106556backstagebackstage+3EPSS score0.26%
Backstage is an open framework for building developer portals. Prior to 1.14.6, the @backstage/plugin-techdocs-node package is affected by configuration bypass in techdocs mkdocs.yml sanitization. Insufficient validation of MkDocs configuration during TechDocs generation could allow an authenticated user who can register or modify documentation sources to execute arbitrary commands in the build environment. Impact is limited to resources accessible to the TechDocs backend or build container. This issue is fixed in versions 1.14.6 and 1.15.4.CVE-2026-106560backstagebackstage+4EPSS score0.31%
Backstage is an open framework for building developer portals. Prior to 0.3.25, the @backstage/plugin-scaffolder-backend-module-confluence-to-markdown package is affected by improper repository path validation in a scaffolder backend module. An authenticated user who can execute an affected template and control its repository file location may cause generated content to be written outside the task workspace, within locations writable by the Backstage backend process. This issue is fixed in version 0.3.25.