CVE-2026-66392
Received
Received - Intake
Improper Certificate Validation in Apache bRPC
Vulnerability report for CVE-2026-66392, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-21
Last updated on: 2026-10-21
Assigner: Apache Software Foundation
Description
Description
Apache bRPC versions before 1.18.0 validate the server certificate chain when client TLS peer verification is enabled, but do not bind the certificate to an expected DNS name or IP address. A network attacker who can redirect or intercept a connection and who possesses a certificate issued by a CA trusted by the client for another name may impersonate the requested TLS endpoint.
Affected Scenarios:
Applications use a bRPC client Channel to connect to an untrusted network with certificate verification enabled and trust a CA that can issue certificates for identities other than the intended endpoint.
How to Fix:
Upgrade to Apache bRPC 1.18.0 and enable VERIFY_PEER with a positive verify_depth. HTTPS Channels automatically verify the certificate against the host in the Channel URL. Callers may set VerifyOptions::expected_peer_name explicitly when the certificate identity differs from the URL host. Alternatively, apply the patch from https://github.com/apache/brpc/pull/3408 .
Note:
The new option performs DNS SAN or IP SAN verification during the TLS handshake. Configurations that set expected_peer_name while peer verification is disabled are rejected.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| Apache | Software | Foundation Apache bRPC 0 |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-297 | The product communicates with a host that provides a certificate, but the product does not properly ensure that the certificate is actually associated with that host. |
