From fc7f71def56cf7fe71387a518e01bf4739ff4106 Mon Sep 17 00:00:00 2001
From: Antigravity Assistant <bot@antigravity.local>
Date: Thu, 30 Apr 2026 02:54:49 -0300
Subject: [PATCH] fix: resolve security ReDoS in codex and bugs #1797 #1789

---
 open-sse/executors/codex.ts   | 25 ++++++++++++++---
 open-sse/handlers/chatCore.ts | 53 ++++++++++++++++++++++++++++++++++-
 2 files changed, 73 insertions(+), 5 deletions(-)

diff --git a/open-sse/executors/codex.ts b/open-sse/executors/codex.ts
index 49c200c8fb..cddc72c25a 100644
--- a/open-sse/executors/codex.ts
+++ b/open-sse/executors/codex.ts
@@ -619,10 +619,27 @@ function normalizeCodexTools(body: Record<string, unknown>): void {
 }
 
 function getResponsesSubpath(endpointPath: unknown): string | null {
-  const normalizedEndpoint = String(endpointPath || "").replace(/\/+$/, "");
-  const match = normalizedEndpoint.match(/(?:^|\/)responses(?:(\/.*))?$/i);
-  if (!match) return null;
-  return match[1] || "";
+  let normalizedEndpoint = String(endpointPath || "");
+  while (normalizedEndpoint.endsWith("/") && normalizedEndpoint.length > 0) {
+    normalizedEndpoint = normalizedEndpoint.slice(0, -1);
+  }
+
+  const lower = normalizedEndpoint.toLowerCase();
+  if (lower === "responses" || lower.endsWith("/responses")) {
+    return "";
+  }
+
+  const responsesSlash = "/responses/";
+  const idx = lower.lastIndexOf(responsesSlash);
+  if (idx !== -1) {
+    return normalizedEndpoint.slice(idx + "/responses".length);
+  }
+
+  if (lower.startsWith("responses/")) {
+    return normalizedEndpoint.slice("responses".length);
+  }
+
+  return null;
 }
 
 export function isCompactResponsesEndpoint(endpointPath: unknown): boolean {
diff --git a/open-sse/handlers/chatCore.ts b/open-sse/handlers/chatCore.ts
index a131a7cbc6..7872b5cc73 100644
--- a/open-sse/handlers/chatCore.ts
+++ b/open-sse/handlers/chatCore.ts
@@ -1696,7 +1696,36 @@ export async function handleChatCore({
   ) => {
     const preserveToolResultBlocks = options?.preserveToolResultBlocks === true;
     if (!Array.isArray(payload.messages)) return;
-    const messages = payload.messages as ClaudeMessage[];
+    let messages = payload.messages as ClaudeMessage[];
+
+    // Extract system role messages (Issue #1797)
+    const systemMessages = messages.filter((m) => m.role === "system");
+    if (systemMessages.length > 0) {
+      const extraBlocks: ClaudeContentBlock[] = [];
+      for (const sm of systemMessages) {
+        if (typeof sm.content === "string" && sm.content.length > 0) {
+          extraBlocks.push({ type: "text", text: sm.content });
+        } else if (Array.isArray(sm.content)) {
+          for (const block of sm.content as ClaudeContentBlock[]) {
+            if (block?.type === "text" && typeof block.text === "string" && block.text.length > 0) {
+              extraBlocks.push(block);
+            }
+          }
+        }
+      }
+      if (extraBlocks.length > 0) {
+        const existingSystem = payload.system;
+        if (typeof existingSystem === "string" && existingSystem.length > 0) {
+          payload.system = [{ type: "text", text: existingSystem }, ...extraBlocks];
+        } else if (Array.isArray(existingSystem)) {
+          payload.system = [...(existingSystem as ClaudeContentBlock[]), ...extraBlocks];
+        } else {
+          payload.system = extraBlocks;
+        }
+      }
+      messages = messages.filter((m) => m.role !== "system");
+      payload.messages = messages;
+    }
 
     // Anthropic rejects empty text blocks in native Messages payloads.
     for (const msg of messages) {
@@ -1969,6 +1998,28 @@ export async function handleChatCore({
   }
   translatedBody.model = finalModelToUpstream;
 
+  // #1789: Prevent output_config.effort from overriding effort encoded in model name (Codex)
+  if (provider === "codex" || provider?.startsWith("codex")) {
+    const hasEffortSuffix = finalModelToUpstream.match(/-(low|medium|high|xhigh)$/i);
+    if (
+      hasEffortSuffix &&
+      translatedBody.output_config &&
+      typeof translatedBody.output_config === "object"
+    ) {
+      const oc = translatedBody.output_config as Record<string, unknown>;
+      if (oc.effort) {
+        log?.warn?.(
+          "PARAMS",
+          `Stripped output_config.effort="${oc.effort}" because model "${finalModelToUpstream}" already encodes effort`
+        );
+        delete oc.effort;
+        if (Object.keys(oc).length === 0) {
+          delete translatedBody.output_config;
+        }
+      }
+    }
+  }
+
   // Strip unsupported parameters for reasoning models (o1, o3, etc.)
   const unsupported = getUnsupportedParams(provider, model);
   if (unsupported.length > 0) {