CVE-2026-33186 — gRPC-Go has an authorization bypass via missing leading slash in :path

Affected: grpc-go, Red Hat Cryostat 4 on RHEL 9, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 10.0 Extended Update Support, Red Hat Enterprise Linux 7 Extended Lifecycle Support, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions, Red Hat Enterprise Linux 9.4 Extended Update Support, Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions and 158 more

gRPC-Go is the Go language implementation of gRPC. Versions prior to 1.79.3 have an authorization bypass resulting from improper input validation of the HTTP/2 `:path` pseudo-header. The gRPC-Go server was too lenient in its routing logic, accepting requests where the `:path` omitted the mandatory leading slash (e.g., `Service/Method` instead of `/Service/Method`). While the server successfully routed these requests to the correct handler, authorization interceptors (including the official `grpc/authz` package) evaluated the raw, non-canonical path string. Consequently, "deny" rules defined using canonical paths (starting with `/`) failed to match the incoming request, allowing it to bypass the policy if a fallback "allow" rule was present. This affects gRPC-Go servers that use path-based authorization interceptors, such as the official RBAC implementation in `google.golang.org/grpc/authz` or custom interceptors relying on `info.FullMethod` or `grpc.Method(ctx)`; AND that have a security policy contains specific "deny" rules for canonical paths but allows other requests by default (a fallback "allow" rule). The vulnerability is exploitable by an attacker who can send raw HTTP/2 frames with malformed `:path` headers directly to the gRPC server. The fix in version 1.79.3 ensures that any request with a `:path` that does not start with a leading slash is immediately rejected with a `codes.Unimplemented` error, preventing it from reaching authorization interceptors or handlers w…

GHSA-c6gw-w398-hv78 — DoS in go-jose Parsing

Affected: Go: github.com/go-jose/go-jose/v4, Go: github.com/go-jose/go-jose/v3, Go: github.com/go-jose/go-jose

### Impact When parsing compact JWS or JWE input, go-jose could use excessive memory. The code used strings.Split(token, ".") to split JWT tokens, which is vulnerable to excessive memory consumption when processing maliciously crafted tokens with a large number of '.' characters. An attacker could exploit this by sending numerous malformed tokens, leading to memory exhaustion and a Denial of Service.

### Patches Version 4.0.5 fixes this issue

### Workarounds Applications could pre-validate payloads passed to go-jose do not contain an excessive number of '.' characters.

### References This is the same sort of issue as in the golang.org/x/oauth2/jws package as CVE-2025-22868 and Go issue https://go.dev/issue/71490.

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CVE-2026-33186 — gRPC-Go has an authorization bypass via missing leading slash in :path

GHSA-c6gw-w398-hv78 — DoS in go-jose Parsing