GitHub Advisoryadvisory · npm

GHSA-656w-6f6c-m9r6 OneUptime has broken access control in GitHub App installation flow that allows unauthorized project binding

HIGH Published 2026-03-09 Modified 2026-03-10 Official page ↗
Aliases
CVE-2026-30920
Ecosystem
npm
Packages
@oneuptime/common
Severity
High
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L
Weaknesses
CWE-345, CWE-639, CWE-862
Reviewed
2026-03-09

Affected packages

• npm @oneuptime/common: < 10.0.19 → fixed in 10.0.19

Description

Summary OneUptime's GitHub App callback trusts attacker-controlled `state` and `installation_id` values and updates `Project.gitHubAppInstallationId` with `isRoot: true` without validating that the caller is authorized for the target project. This allows an attacker to overwrite another project's GitHub App installation binding. Related GitHub endpoints also lack effective authorization, so a valid installation ID can be used to enumerate repositories and create `CodeRepository` records in an arbitrary project. Details The callback decodes unsigned base64 JSON from `state` and uses the embedded `projectId` directly: • https://github.com/OneUptime/oneuptime/blob/master/Common/Server/API/GitHubAPI.ts#L34-L112 It then writes the supplied `installation_id` into the target project with root privileges: ```ts await ProjectService.updateOneById({ id: new ObjectID(projectId), data: { gitHubAppInstallationId: installationId }, props: { isRoot: true }, }); ``` The `userId` in `state` is only checked for presence, not authenticity: • https://github.com/OneUptime/oneuptime/blob/master/Common/Server/API/GitHubAPI.ts#L73-L79 The install flow also generates `state` as plain base64 JSON, not a signed or session-bound token: • https://github.com/OneUptime/oneuptime/blob/master/Common/Server/API/GitHubAPI.ts#L127-L165 The follow-on endpoints are also vulnerable: • Repository listing: https://github.com/OneUptime/oneuptime/blob/master/Common/Server/API/GitHubAPI.ts#L179-L258 • Repository connect: https://github.com/OneUptime/oneuptime/blob/master/Common/Server/API/GitHubAPI.ts#L260-L356 • Middleware allows requests with no token to continue as `Public`: https://github.com/OneUptime/oneuptime/blob/master/Common/Server/Middleware/UserAuthorization.ts#L205-L211 • Installation tokens are minted from any valid installation ID: https://github.com/OneUptime/oneuptime/blob/master/Common/Server/Utils/CodeRepository/GitHub/GitHub.ts#L347-L425 PoC Minimal proof of unauthorized project tampering: ```bash STATE=$(printf '%s' '{"projectId":"","userId":"x"}' | base64 | tr -d '\n') curl -isk "https:///api/github/auth/callback?installation_id=999999999&state=${STATE}" ``` Expected result: • Server returns a `302` redirect to `/dashboard//code-repository?installation_id=999999999` • The target project's `gitHubAppInstallationId` is overwritten Impact • Unauthorized modification of `Project.gitHubAppInstallationId` • Temporary GitHub integration breakage if a bogus installation ID is set • Cross-project binding of attacker-controlled GitHub App installations • Repository metadata disclosure for a supplied valid installation ID • Unauthorized creation of `CodeRepository` records in arbitrary projects

Related

Alias · CVE (1)

  • CVE-2026-30920 OneUptime is a solution for monitoring and managing online services. vulnerability

Weakness · CWE (3)

  • CWE-345 Insufficient Verification of Data Authenticity weakness
  • CWE-639 Authorization Bypass Through User-Controlled Key weakness
  • CWE-862 Missing Authorization weakness

References