CVE-2026-59891

CRITICAL

Credential confusion in  @sigstore/oci  can leak registry credentials to an attacker-controlled registry

Title source: cna
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2026-59891. PoCs published by gyubin02.

AI-analyzed exploit summary This repository provides a detailed technical analysis and regression test suite for CVE-2026-59891, a credential selection vulnerability in the @sigstore/oci library (versions <= 0.7.0). The code demonstrates the vulnerability by showing how credentials are incorrectly selected and transmitted to unintended registries due to improper host matching in Docker config auths.

Description

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.

Exploits (1)

nomisec WRITEUP
by gyubin02 · poc
https://github.com/gyubin02/cve-2026-59891-control-lab

This repository provides a detailed technical analysis and regression test suite for CVE-2026-59891, a credential selection vulnerability in the @sigstore/oci library (versions <= 0.7.0). The code demonstrates the vulnerability by showing how credentials are incorrectly selected and transmitted to unintended registries due to improper host matching in Docker config auths.

Classification
Writeup 98%
Attack Type
Info Leak
Complexity
Moderate
Reliability
Reliable
Target: @sigstore/oci versions <= 0.7.0
Auth required
Prerequisites: Access to a Docker config with credentials · Use of a vulnerable @sigstore/oci version (<= 0.7.0) · Interaction with a registry where credentials could be leaked
mistral-large-3 · analyzed Jul 28, 2026 Full analysis →

Scores

CVSS v3 9.6
EPSS 0.0032
EPSS Percentile 24.0%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact total

Details

CWE
CWE-522
Status published
Products (2)
sigstore/oci 0 - 0.7.1npm
sigstore/sigstore-js < 0.7.1
Published Jul 14, 2026
Tracked Since Jul 14, 2026