GitHub Advisoryadvisory · npm
GHSA-656w-6f6c-m9r6 OneUptime has broken access control in GitHub App installation flow that allows unauthorized project binding
HIGH
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
References
- https://github.com/OneUptime/oneuptime/security/advisories/GHSA-656w-6f6c-m9r6 web
- https://nvd.nist.gov/vuln/detail/CVE-2026-30920 advisory
- https://github.com/OneUptime/oneuptime package
- https://github.com/OneUptime/oneuptime/blob/master/Common/Server/API/GitHubAPI.ts#L127-L165 web
- https://github.com/OneUptime/oneuptime/blob/master/Common/Server/API/GitHubAPI.ts#L179-L258 web
- https://github.com/OneUptime/oneuptime/blob/master/Common/Server/API/GitHubAPI.ts#L260-L356 web
- https://github.com/OneUptime/oneuptime/blob/master/Common/Server/API/GitHubAPI.ts#L34-L112 web
- https://github.com/OneUptime/oneuptime/blob/master/Common/Server/API/GitHubAPI.ts#L73-L79 web
- https://github.com/OneUptime/oneuptime/blob/master/Common/Server/Middleware/UserAuthorization.ts#L205-L211 web
- https://github.com/OneUptime/oneuptime/blob/master/Common/Server/Utils/CodeRepository/GitHub/GitHub.ts#L347-L425 web