@sigstore/oci sends the registry Authorization header to a cross-host blob-upload Location

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.4 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N

EPSS

• CVE-2026-118763: 0.30% estimated exploitation activity in the next 30 days; percentile 22.77 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary @sigstore/oci sends the registry Authorization header to a cross-host blob-upload Location

Affected versions and vulnerable location - Confirmed on sigstore-js at `3a83271` (current HEAD). - File: `packages/oci/src/registry.ts`. - `signIn()` installs the credential as a DEFAULT header on the shared client: `this.#fetch = this.#fetch.defaults({ headers: { [HEADER_AUTHORIZATION]: 'Basic ' + basicAuth } })` (`:126-128`) or `... 'Bearer ' + token` (`:145-147`), plus `creds.headers` from the Docker config (`:104`). - `uploadBlob()` reads the `Location` response header (`:184`), builds `uploadLocation = new URL(location.startsWith('/') ? this.#baseURL + location : location)` (`:190-192`), and PUTs the blob to it through the same client: `await this.#fetch(uploadLocation.href, { method: 'PUT', body: blob, headers: { [HEADER_CONTENT_TYPE]: ... } })` (`:198`). - There is no check that `uploadLocation`'s host (or scheme) equals the registry host before the PUT is sent.

Root…

Published by the source

30 Oct 2026, 23:00 UTC

Last modified by the source

30 Oct 2026, 23:15 UTC

Source last checked

31 Oct 2026, 06:00 UTC

1. Revision 2 · amended · 31 Oct 2026

   Amended from osv record GHSA-j63v-mwhm-56jx

2. Revision 1 · created · 30 Oct 2026

   Published from ghsa record GHSA-j63v-mwhm-56jx

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# Patch Next advisory brief: CVE-2026-118763

Advisory: @sigstore/oci sends the registry Authorization header to a cross-host blob-upload Location
IDs: CVE-2026-118763, GHSA-j63v-mwhm-56jx
Record: https://patchnext.com/advisories/cve-2026-118763 (revision 2, source checked 31 Oct 2026, 06:00 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.4)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: @sigstore/oci 0.7.2. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm @sigstore/oci: affected < 0.7.2; fixed in 0.7.2

## Suggested inspection (read-only)
- `npm ls @sigstore/oci --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on @sigstore/oci.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-j63v-mwhm-56jx (GitHub-reviewed advisory GHSA-j63v-mwhm-56jx lists affected ranges: npm @sigstore/oci >=0 <=0.7.1)
- Verified: https://osv.dev/vulnerability/GHSA-j63v-mwhm-56jx (OSV record GHSA-j63v-mwhm-56jx lists affected ranges: npm @sigstore/oci >=0 <0.7.2 (fixed))

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