CVE-2026-57449 (GCVE-0-2026-57449)

Vulnerability from cvelistv5 – Published: 2026-09-25 22:10 – Updated: 2026-09-25 22:10
VLAI
Title
Actual Sync Server: CORS Proxy GitHub API Allowlist Prefix Bypass Leaks Private Repositories Through the Server GitHub Token
Summary
Actual is a local-first personal finance tool. Prior to 26.7.0, Actual Sync Server's CORS proxy is intended to let authenticated users fetch resources only from repositories listed in the official plugin allowlist. When `ACTUAL_GITHUB_TOKEN` is configured, the proxy automatically attaches the server's GitHub token to GitHub requests. The GitHub API allowlist check uses a raw `startsWith()` prefix test for `/repos/{owner}/{repo}` without requiring a path boundary after the repository name. If an allowlisted public plugin repository is `https://github.com/acme/plugin`, the proxy also accepts GitHub API URLs. Those URLs are outside the allowlisted repository but still pass because their API path starts with `/repos/acme/plugin`. The proxy then forwards the request with the server's `ACTUAL_GITHUB_TOKEN`, allowing any authenticated Actual user to read private GitHub resources reachable by that token. Version 26.7.0 fixes the issue.
Severity
7.1 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
CWE
  • CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
  • CWE-284 - Improper Access Control
  • CWE-863 - Incorrect Authorization
Assigner
References
Impacted products
Vendor Product Version CPE status
actualbudget actual Affected: < 26.7.0
guessed Create a notification for this product.
Show details on NVD website
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        "dateUpdated": "2026-09-25T22:10:39.706Z",
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        "shortName": "GitHub_M"
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      "source": {
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        "discovery": "UNKNOWN"
      },
      "title": "Actual Sync Server: CORS Proxy GitHub API Allowlist Prefix Bypass Leaks Private Repositories Through the Server GitHub Token"
    }
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    "dateReserved": "2026-06-24T13:21:20.730Z",
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          }
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}



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