GHSA-j9v4-rhgr-4m5f

Suggest an improvement
Source
https://github.com/advisories/GHSA-j9v4-rhgr-4m5f
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/09/GHSA-j9v4-rhgr-4m5f/GHSA-j9v4-rhgr-4m5f.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-j9v4-rhgr-4m5f
Aliases
Published
2026-09-17T14:52:37Z
Modified
2026-09-17T15:00:05Z
Severity
  • 6.3 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N CVSS Calculator
Summary
oRPC: Vary Header Injection in CORS Plugin leading to potential Cache/CORS Bypass
Details

Summary

A flaw in the CORS plugin allowed the incoming request's Vary header to be reflected into the response, letting a client influence a header that should be controlled solely by the server.

Details

The CORS plugin previously copied the request's Vary header directly onto the response instead of treating Vary as a response-only header. Because Vary tells downstream caches and proxies how to key their cached responses, this allowed a client to inject arbitrary values into the response's Vary header, potentially distorting cache-key behavior in shared caches/CDNs sitting in front of an oRPC server and leading to inconsistent CORS enforcement for other clients.

Practical impact is limited to deployments where a shared cache or reverse proxy keys on the Vary header; the real-world effect depends on the caching layer's configuration.

Impact

May cause cache key pollution and inconsistent CORS enforcement in setups that rely on shared/edge caches keying on Vary. No direct confidentiality, integrity, or availability impact in default (non-cached) configurations.

Resolution

Update @orpc/server (and any other @orpc/* packages bundling the CORS plugin) to 1.14.8. The CORS plugin now derives Vary exclusively from the response, appending Origin and preserving existing values instead of reflecting request headers.

Database specific 
{
    "cwe_ids": [
        "CWE-113"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-09-17T14:52:37Z",
    "nvd_published_at": "2026-09-16T19:17:38Z",
    "severity": "MODERATE"
}
References

Affected packages

npm / @orpc/server

Package

Name
@orpc/server
View open source insights on deps.dev
Purl
pkg:npm/%40orpc/server

Affected ranges

Type
SEMVER
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
1.14.8

Database specific

last_known_affected_version_range 
"<= 1.14.7"
source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/09/GHSA-j9v4-rhgr-4m5f/GHSA-j9v4-rhgr-4m5f.json"