Vulnerability · Published Aug 20, 2026 · Assigned by GitHub_M

CVE-2026-50192Kerberos Hub private key (X-Kerberos-Hub-PrivateKey) leaked to cross-host redirect target due to redirect-following HTTP client without CheckRedirect

Medium 6.9

In plain English

A medium-severity information exposure in agent from kerberos-io. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 37% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)6.9Medium
Exploit odds (30 days)0.4%top 63.3% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official description

Kerberos Agent is an open source video (surveillance) management agent. Prior to version 3.6.26, the Kerberos Hub upload path sends the agent's Hub credentials in the custom `X-Kerberos-Hub-PrivateKey` and `X-Kerberos-Hub-PublicKey` request headers to the operator-configured Hub URL (`config.HubURI`). The HTTP client used (`&http.Client{}` in `UploadKerberosHub`) is constructed without a `CheckRedirect` policy, so it follows HTTP redirects automatically. Go's `net/http` strips only sensitive headers (`Authorization`, `Cookie`, `WWW-Authenticate`) on a cross-host redirect; it does not strip custom headers such as `X-Kerberos-Hub-PrivateKey`. As a result, if the configured `HubURI` returns a cross-host 30x redirect, the Hub private key is forwarded verbatim to the redirect target, disclosing the credential to an unintended third party. Version 3.6.26 fixes the issue by implementing the `CheckRedirect` strip plus a cross-host regression test is provided to the maintainer through the advisory's private temporary fork.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Gogithub.com/kerberos-io/agent/machinery0.0.0-20260528173546-51f1a52e170fGHSA-h5gx-45rj-2h5j
Gogithub.com/kerberos-io/agent/machinery0.0.0-20260528173546-51f1a52e170fGO-2026-5890

Affected products (as reported)

VendorProductVersions
kerberos-io agent < 3.6.26

Weakness: CWE-200, CWE-522 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

References