Medium severity · published Sep 16, 2026
CVE-2026-77360
oRPC: Vary Header Injection in CORS Plugin leading to potential Cache/CORS Bypass
6.3
CVSS
0.5%
EPSS
No
On KEV
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 45% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OR
orpc · middleapi
< 1.14.8 · source: vendor