---
title: "CVE-2026-59891: Credential confusion in @sigstore/oci can leak registry credentials to an attacker-controlled registry"
url: https://erroneo.us/security/cve/CVE-2026-59891/
description: "CVE-2026-59891 (@sigstore/oci (npm)): sigstore-js provides JavaScript libraries for interacting with Sigstore services. Prior to 0.7.1…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-07-14
date_modified: 2026-07-21
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-59891"
kev: false
cvss: 9.6
epss: 0.00473
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-59891: Credential confusion in @sigstore/oci can leak registry credentials to an attacker-controlled registry

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.5% , percentile 40: FIRST’s model estimates a 0.5% chance of exploitation activity in the next 30 days, higher than 40% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Needs a user to click or open something. Phishing makes that realistic, but it is not wormable.
- Only applies if your dependency tree includes @sigstore/oci (npm) < 0.7.1, fixed in 0.7.1 . Check your lockfile, including transitive dependencies.

## What it is

sigstore-js provides JavaScript libraries for interacting with Sigstore services. Prior to 0.7.1, getRegistryCredentials() reads credentials from the Docker config file and selects an entry by checking whether any configured auth key contains the target registry string. Because this is a substring match rather than an exact host match, credentials configured for one registry can be selected for and transmitted to a different registry whose hostname has a substring relationship with a configured auth key. This issue is fixed in version 0.7.1.

## Affected packages

- npm `@sigstore/oci` < 0.7.1 → fixed: 0.7.1

## Affected products (CVE record)

- sigstore sigstore-js: < 0.7.1

## Severity

- GitHub_M CVSS 3.1: 9.6 `CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H`
- GitHub CVSS 3.1: 9.6 `CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable no , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.47% probability of exploitation activity in the next 30 days; percentile 40.

## Sources

- [GitHub Advisory GHSA-pf56-329r-95rw](https://github.com/advisories/GHSA-pf56-329r-95rw)
- [CVE.org record CVE-2026-59891](https://www.cve.org/CVERecord?id=CVE-2026-59891)
- [NVD entry CVE-2026-59891](https://nvd.nist.gov/vuln/detail/CVE-2026-59891)
- [github.com](https://github.com/sigstore/sigstore-js/security/advisories/GHSA-pf56-329r-95rw)
- [github.com](https://github.com/sigstore/sigstore-js/commit/85c58380758b97ce1b74ef470e55cc21f9d3aa89)
- [github.com](https://github.com/sigstore/sigstore-js/releases/tag/%40sigstore%2Foci%400.7.1)

---
Source page: https://erroneo.us/security/cve/CVE-2026-59891/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt