External Control of File Name or Path Affecting @backstage/backend-defaults package, versions <0.17.8
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published11 Oct 2026
- disclosed7 Oct 2026
- creditUnknown
Introduced: 7 Oct 2026
NewCVE-2026-106494 (opens in a new tab)How to fix?
Upgrade @backstage/backend-defaults to version 0.17.8 or higher.
Overview
@backstage/backend-defaults is a Backend defaults used by Backstage backend apps
Affected versions of this package are vulnerable to External Control of File Name or Path via the cloud storage URL reader implementations (AwsS3UrlReader, AwsCodeCommitUrlReader, AzureBlobStorageUrlReader, and GoogleGcsUrlReader) when processing object or blob names that contain dot path segments (. or ..). An attacker who can influence the names of objects stored in a cloud storage bucket or repository can cause the reader to traverse outside the intended directory, potentially writing or overwriting files at unintended paths on the server.