CVE-2026-77360 oRPC: Vary Header Injection in CORS Plugin leading to potential Cache/CORS Bypass
Attackers can inject Vary headers to pollute cache keys and bypass CORS enforcement in cached deployments of the oRPC server library.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-77360?
CVE-2026-77360 is a medium-severity vulnerability in middleapi orpc, published on 16 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
oRPC is an tool that helps build APIs that are end-to-end type-safe and adhere to OpenAPI standards. Prior to 1.14.8, the @orpc/server CORS plugin in packages/server/src/plugins/cors.ts copies a client's incoming Vary request header into the response instead of controlling Vary as a response-only header and using Origin for request-origin variation. In deployments behind a shared cache, CDN, or reverse proxy that keys responses using Vary, a client can inject arbitrary variation values, pollute cache keys, and cause inconsistent CORS enforcement for other clients. Default non-cached configurations have no established direct confidentiality, integrity, or availability impact. This issue is fixed in version 1.14.8.
Weakness: CWE-113
Which versions are affected by CVE-2026-77360?
2 open source packages ship an affected version, including @orpc/server.
| Package | Affected | Fixed in |
|---|---|---|
@orpc/server npm | All versions | 1.14.8 |
@orpc/server npm | All versions | 1.14.8 |
How do I fix CVE-2026-77360?
Upgrade @orpc/server to 1.14.8 or later.
Is CVE-2026-77360 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-77360 exists.
Sources
Also known as GHSA-j9v4-rhgr-4m5f.