diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5b121bddb0..9bd03e72c3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -29,6 +29,7 @@
 - CLI: add `codexbar serve` for localhost JSON access to usage and cost endpoints (#957). Thanks @ThiagoCAltoe!
 
 ### Fixed
+- OpenCode Go: block cross-host redirects when fetching usage so imported cookies cannot follow external redirect targets (#969). Thanks @pavbar!
 - Codex: keep background `/status` probes out of Codex Desktop history by using isolated non-persistent CLI storage (#953).
 - Menu: stabilize the Cost submenu by using a native menu item and deferring open-menu rebuilds while tracking (#954). Thanks @getogrand!
 - Localization: add Brazilian Portuguese quota-warning settings strings (#958). Thanks @ThiagoCAltoe!
diff --git a/Sources/CodexBarCore/Providers/OpenCodeGo/OpenCodeGoUsageFetcher.swift b/Sources/CodexBarCore/Providers/OpenCodeGo/OpenCodeGoUsageFetcher.swift
index 1f5c28d146..efd6aac716 100644
--- a/Sources/CodexBarCore/Providers/OpenCodeGo/OpenCodeGoUsageFetcher.swift
+++ b/Sources/CodexBarCore/Providers/OpenCodeGo/OpenCodeGoUsageFetcher.swift
@@ -33,6 +33,25 @@ public struct OpenCodeGoUsageFetcher: Sendable {
         "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) " +
         "AppleWebKit/537.36 (KHTML, like Gecko) Chrome/143.0.0.0 Safari/537.36"
 
+    private final class RedirectGuardDelegate: NSObject, URLSessionTaskDelegate {
+        func urlSession(
+            _ session: URLSession,
+            task: URLSessionTask,
+            willPerformHTTPRedirection response: HTTPURLResponse,
+            newRequest request: URLRequest,
+            completionHandler: @escaping (URLRequest?) -> Void)
+        {
+            guard OpenCodeGoUsageFetcher.allowsRedirect(
+                from: task.originalRequest?.url,
+                to: request.url)
+            else {
+                completionHandler(nil)
+                return
+            }
+            completionHandler(request)
+        }
+    }
+
     private struct ServerRequest {
         let serverID: String
         let args: String?
@@ -73,14 +92,24 @@ public struct OpenCodeGoUsageFetcher: Sendable {
         "renewAt",
         "renew_at",
     ]
+    private static let redirectGuardDelegate = RedirectGuardDelegate()
+    private static let redirectGuardSession: URLSession = {
+        let configuration = URLSessionConfiguration.ephemeral
+        configuration.httpCookieStorage = nil
+        return URLSession(
+            configuration: configuration,
+            delegate: OpenCodeGoUsageFetcher.redirectGuardDelegate,
+            delegateQueue: nil)
+    }()
 
     public static func fetchUsage(
         cookieHeader: String,
         timeout: TimeInterval,
         now: Date = Date(),
         workspaceIDOverride: String? = nil,
-        session: URLSession = .shared) async throws -> OpenCodeGoUsageSnapshot
+        session: URLSession? = nil) async throws -> OpenCodeGoUsageSnapshot
     {
+        let session = session ?? self.redirectGuardSession
         guard let requestCookieHeader = OpenCodeWebCookieSupport.requestCookieHeader(from: cookieHeader) else {
             throw OpenCodeGoUsageError.invalidCredentials
         }
@@ -100,6 +129,15 @@ public struct OpenCodeGoUsageFetcher: Sendable {
         return try self.parseSubscription(text: subscriptionText, now: now)
     }
 
+    static func allowsRedirect(from sourceURL: URL?, to destinationURL: URL?) -> Bool {
+        guard let sourceHost = sourceURL?.host?.lowercased(),
+              let destinationHost = destinationURL?.host?.lowercased(),
+              sourceHost == destinationHost,
+              destinationURL?.scheme?.lowercased() == "https"
+        else { return false }
+        return true
+    }
+
     public static func dashboardURL(workspaceID raw: String?) -> URL {
         guard let workspaceID = self.normalizeWorkspaceID(raw),
               let url = URL(string: "\(self.baseURL.absoluteString)/workspace/\(workspaceID)/go")
diff --git a/Tests/CodexBarTests/OpenCodeGoUsageFetcherErrorTests.swift b/Tests/CodexBarTests/OpenCodeGoUsageFetcherErrorTests.swift
index 12c73ab773..585741ca7c 100644
--- a/Tests/CodexBarTests/OpenCodeGoUsageFetcherErrorTests.swift
+++ b/Tests/CodexBarTests/OpenCodeGoUsageFetcherErrorTests.swift
@@ -1,6 +1,6 @@
-import CodexBarCore
 import Foundation
 import Testing
+@testable import CodexBarCore
 
 @Suite(.serialized)
 struct OpenCodeGoUsageFetcherErrorTests {
@@ -28,6 +28,21 @@ struct OpenCodeGoUsageFetcherErrorTests {
         return URLSession(configuration: config)
     }
 
+    @Test
+    func `redirect guard allows only same-host https redirects`() {
+        #expect(OpenCodeGoUsageFetcher.allowsRedirect(
+            from: URL(string: "https://opencode.ai/_server"),
+            to: URL(string: "https://opencode.ai/workspace/wrk_TEST123/go")))
+
+        #expect(!OpenCodeGoUsageFetcher.allowsRedirect(
+            from: URL(string: "https://opencode.ai/_server"),
+            to: URL(string: "https://evil.example/steal")))
+
+        #expect(!OpenCodeGoUsageFetcher.allowsRedirect(
+            from: URL(string: "https://opencode.ai/_server"),
+            to: URL(string: "http://opencode.ai/insecure")))
+    }
+
     @Test
     func `extracts api error from detail field`() async throws {
         defer {