fix(security): harden API against pentest findings

- Default TRUST_PROXY=false to prevent XFF rate limit bypass (PT-01)
- Return 400 instead of 500 on malformed JSON input (PT-03)
- Default MAX_PIPELINE_STEPS=20 to prevent DoS (PT-04)
- Validate clientJobId length (max 128) across all routes (PT-06)
- Add security headers to all reply.hijack() streaming responses (PT-07)
- Sanitize usernames in audit log to prevent stored XSS (PT-08)
- Block TRACE method with 405 response (PT-10)
- Add 429 RateLimited response to OpenAPI spec (PT-12)
- Default MAX_SVG_SIZE_MB=50 to limit SVGZ decompression (PT-13)
- Pin Dockerfile base images by digest
- Sanitize OIDC IdP error and sub claim in audit log
- Sync Docker compose/Dockerfile defaults with env.ts

apps/api/src/index.ts

@@ -137,8 +137,10 @@ app.addContentTypeParser("application/json", { parseAs: "string" }, (_request, b
   try {
     const str = typeof body === "string" ? body : (body as Buffer).toString();
     done(null, str.length > 0 ? JSON.parse(str) : {});
-  } catch (err) {
-    done(err as Error, undefined);
+  } catch {
+    const parseErr = new Error("Malformed JSON in request body") as Error & { statusCode: number };
+    parseErr.statusCode = 400;
+    done(parseErr, undefined);
   }
 });
 
@@ -188,6 +190,13 @@ await app.register(rateLimit, {
   allowList: (request) => !request.url.startsWith("/api/"),
 });
 
+// Block TRACE method (returns 401 instead of 405 without this)
+app.addHook("onRequest", async (request, reply) => {
+  if (request.method === "TRACE") {
+    return reply.status(405).send({ error: "Method not allowed" });
+  }
+});
+
 // Multipart upload support
 await registerUpload(app);
 

apps/api/src/lib/audit.ts

@@ -2,6 +2,12 @@ import { randomUUID } from "node:crypto";
 import type { FastifyBaseLogger } from "fastify";
 import { db, schema } from "../db/index.js";
 
+const MAX_AUDIT_INPUT_LENGTH = 200;
+
+export function sanitizeAuditInput(raw: string): string {
+  return raw.replace(/[<>&"']/g, "").slice(0, MAX_AUDIT_INPUT_LENGTH) || "(empty)";
+}
+
 type AuditEvent =
   | "LOGIN_SUCCESS"
   | "LOGIN_FAILED"

apps/api/src/lib/csp.ts

@@ -25,3 +25,15 @@ export function buildCsp(isDocs: boolean): string {
 
   return `default-src 'self'; script-src ${scriptSrc}; style-src 'self' 'unsafe-inline'; img-src 'self' blob: data: https://tile.openstreetmap.org; connect-src ${connectSrc}; font-src ${fontSrc}; object-src 'none'; frame-ancestors 'none'; base-uri 'self'; form-action 'self'`;
 }
+
+export function getSecurityHeaders(): Record<string, string> {
+  return {
+    "X-Content-Type-Options": "nosniff",
+    "X-Frame-Options": "DENY",
+    "X-XSS-Protection": "0",
+    "Referrer-Policy": "strict-origin-when-cross-origin",
+    "Permissions-Policy": "camera=(), microphone=(), geolocation=()",
+    "Strict-Transport-Security": "max-age=31536000; includeSubDomains",
+    "Content-Security-Policy": buildCsp(false),
+  };
+}

apps/api/src/lib/env.ts

@@ -44,9 +44,9 @@ const envSchema = z
     LOG_LEVEL: z.enum(["fatal", "error", "warn", "info", "debug", "trace"]).default("info"),
     MAX_WORKER_THREADS: z.coerce.number().default(0),
     PROCESSING_TIMEOUT_S: z.coerce.number().default(0),
-    MAX_PIPELINE_STEPS: z.coerce.number().default(0),
+    MAX_PIPELINE_STEPS: z.coerce.number().default(20),
     MAX_CANVAS_PIXELS: z.coerce.number().default(0),
-    MAX_SVG_SIZE_MB: z.coerce.number().default(0),
+    MAX_SVG_SIZE_MB: z.coerce.number().default(50),
     MAX_SPLIT_GRID: z.coerce.number().default(100),
     MAX_STORAGE_PER_USER_MB: z.coerce.number().default(5000),
     MAX_WORKSPACE_SIZE_GB: z.coerce.number().default(10),
@@ -55,7 +55,7 @@ const envSchema = z
     LOGIN_ATTEMPT_LIMIT: z.coerce.number().default(30),
     TRUST_PROXY: z
       .enum(["true", "false"])
-      .default("true")
+      .default("false")
       .transform((v) => v === "true"),
     OIDC_ENABLED: z
       .enum(["true", "false"])

apps/api/src/openapi.yaml

@@ -59,6 +59,31 @@ components:
       scheme: bearer
       description: Session token from login or API key (prefixed with si_)
 
+  responses:
+    RateLimited:
+      description: Too many requests. The client has exceeded the rate limit.
+      headers:
+        Retry-After:
+          schema:
+            type: integer
+          description: Seconds until the rate limit window resets
+        X-RateLimit-Limit:
+          schema:
+            type: integer
+          description: Maximum requests per time window
+        X-RateLimit-Remaining:
+          schema:
+            type: integer
+          description: Remaining requests in current window
+      content:
+        application/json:
+          schema:
+            type: object
+            properties:
+              error:
+                type: string
+                example: Rate limit exceeded
+
   schemas:
     Error:
       type: object

apps/api/src/plugins/auth.ts

@@ -5,7 +5,7 @@ import type { FastifyInstance, FastifyReply, FastifyRequest } from "fastify";
 import { z } from "zod";
 import { env } from "../config.js";
 import { db, schema } from "../db/index.js";
-import { auditLog } from "../lib/audit.js";
+import { auditLog, sanitizeAuditInput } from "../lib/audit.js";
 import { getPermissions, requirePermission } from "../permissions.js";
 
 const scryptAsync = promisify(scrypt);
@@ -221,13 +221,19 @@ export async function authRoutes(app: FastifyInstance): Promise<void> {
         .get();
 
       if (!user || !user.passwordHash) {
-        auditLog(request.log, "LOGIN_FAILED", { username: body.username, reason: "unknown_user" });
+        auditLog(request.log, "LOGIN_FAILED", {
+          username: sanitizeAuditInput(body.username),
+          reason: "unknown_user",
+        });
         return reply.status(401).send({ error: "Invalid credentials" });
       }
 
       const valid = await verifyPassword(body.password, user.passwordHash);
       if (!valid) {
-        auditLog(request.log, "LOGIN_FAILED", { username: body.username, reason: "bad_password" });
+        auditLog(request.log, "LOGIN_FAILED", {
+          username: sanitizeAuditInput(body.username),
+          reason: "bad_password",
+        });
         return reply.status(401).send({ error: "Invalid credentials" });
       }
 

apps/api/src/plugins/oidc.ts

@@ -5,7 +5,7 @@ import type { FastifyInstance, FastifyReply, FastifyRequest } from "fastify";
 import * as oidc from "openid-client";
 import { env } from "../config.js";
 import { db, schema } from "../db/index.js";
-import { auditLog } from "../lib/audit.js";
+import { auditLog, sanitizeAuditInput } from "../lib/audit.js";
 import { createSessionToken } from "./auth.js";
 
 // ── Types ─────────────────────────────────────────────────────────
@@ -229,7 +229,9 @@ export async function oidcRoutes(app: FastifyInstance): Promise<void> {
         { error: query.error, description: query.error_description },
         "OIDC IdP returned error",
       );
-      auditLog(request.log, "OIDC_LOGIN_FAILED", { reason: query.error });
+      auditLog(request.log, "OIDC_LOGIN_FAILED", {
+        reason: sanitizeAuditInput(String(query.error)),
+      });
       return redirectToLogin(reply, "oidc_auth_failed");
     }
 
@@ -370,7 +372,10 @@ export async function oidcRoutes(app: FastifyInstance): Promise<void> {
     // 4d. No user found and no auto-create
     if (!userId) {
       request.log.warn({ sub, email }, "OIDC user not authorized");
-      auditLog(request.log, "OIDC_LOGIN_FAILED", { reason: "user_not_authorized", sub });
+      auditLog(request.log, "OIDC_LOGIN_FAILED", {
+        reason: "user_not_authorized",
+        sub: sanitizeAuditInput(String(sub)),
+      });
       return redirectToLogin(reply, "oidc_user_not_authorized");
     }
 

apps/api/src/routes/batch.ts

@@ -16,6 +16,7 @@ import PQueue from "p-queue";
 import sharp from "sharp";
 import { env } from "../config.js";
 import { autoOrient } from "../lib/auto-orient.js";
+import { getSecurityHeaders } from "../lib/csp.js";
 import { resolveConcurrency } from "../lib/env.js";
 import { formatZodErrors } from "../lib/errors.js";
 import { isToolInstalled } from "../lib/feature-status.js";
@@ -84,7 +85,10 @@ export async function registerBatchRoutes(app: FastifyInstance): Promise<void> {
           } else if (part.fieldname === "settings") {
             settingsRaw = part.value as string;
           } else if (part.fieldname === "clientJobId") {
-            clientJobId = part.value as string;
+            const raw = part.value as string;
+            if (typeof raw === "string" && raw.length > 0 && raw.length <= 128) {
+              clientJobId = raw;
+            }
           }
         }
       } catch (err) {
@@ -269,6 +273,7 @@ export async function registerBatchRoutes(app: FastifyInstance): Promise<void> {
         "Transfer-Encoding": "chunked",
         "X-Job-Id": jobId,
         "X-File-Results": encodeURIComponent(JSON.stringify(fileResultsMap)),
+        ...getSecurityHeaders(),
       });
 
       const archive = archiver("zip", { zlib: { level: 5 } });

apps/api/src/routes/pipeline.ts

@@ -19,6 +19,7 @@ import { env } from "../config.js";
 import { db, schema } from "../db/index.js";
 import { trackEvent } from "../lib/analytics.js";
 import { autoOrient } from "../lib/auto-orient.js";
+import { getSecurityHeaders } from "../lib/csp.js";
 import { resolveConcurrency } from "../lib/env.js";
 import { formatZodErrors } from "../lib/errors.js";
 import { isToolInstalled } from "../lib/feature-status.js";
@@ -91,7 +92,10 @@ export async function registerPipelineRoutes(app: FastifyInstance): Promise<void
         } else if (part.fieldname === "pipeline") {
           pipelineRaw = part.value as string;
         } else if (part.fieldname === "clientJobId") {
-          clientJobId = part.value as string;
+          const raw = part.value as string;
+          if (typeof raw === "string" && raw.length > 0 && raw.length <= 128) {
+            clientJobId = raw;
+          }
         }
       }
     } catch (err) {
@@ -476,7 +480,10 @@ export async function registerPipelineRoutes(app: FastifyInstance): Promise<void
         } else if (part.fieldname === "pipeline") {
           pipelineRaw = part.value as string;
         } else if (part.fieldname === "clientJobId") {
-          clientJobId = part.value as string;
+          const raw = part.value as string;
+          if (typeof raw === "string" && raw.length > 0 && raw.length <= 128) {
+            clientJobId = raw;
+          }
         }
       }
     } catch (err) {
@@ -732,6 +739,7 @@ export async function registerPipelineRoutes(app: FastifyInstance): Promise<void
       "Transfer-Encoding": "chunked",
       "X-Job-Id": jobId,
       "X-File-Results": encodeURIComponent(JSON.stringify(fileResultsMap)),
+      ...getSecurityHeaders(),
     });
 
     const archive = archiver("zip", { zlib: { level: 5 } });

apps/api/src/routes/progress.ts

@@ -11,6 +11,7 @@
 import { eq } from "drizzle-orm";
 import type { FastifyInstance, FastifyReply, FastifyRequest } from "fastify";
 import { db, schema } from "../db/index.js";
+import { getSecurityHeaders } from "../lib/csp.js";
 
 export interface JobProgress {
   jobId: string;
@@ -230,6 +231,7 @@ export async function registerProgressRoutes(app: FastifyInstance): Promise<void
         "Cache-Control": "no-cache",
         Connection: "keep-alive",
         "X-Accel-Buffering": "no",
+        ...getSecurityHeaders(),
       });
 
       // Helper to send an SSE message

apps/api/src/routes/tool-factory.ts

@@ -147,7 +147,10 @@ export function createToolRoute<T>(app: FastifyInstance, config: ToolRouteConfig
               fileId = part.value as string;
             }
             if (part.fieldname === "clientJobId") {
-              clientJobId = part.value as string;
+              const raw = part.value as string;
+              if (typeof raw === "string" && raw.length > 0 && raw.length <= 128) {
+                clientJobId = raw;
+              }
             }
           }
         }

apps/api/src/routes/tools/bulk-rename.ts

@@ -3,6 +3,7 @@ import { extname } from "node:path";
 import archiver from "archiver";
 import type { FastifyInstance } from "fastify";
 import { z } from "zod";
+import { getSecurityHeaders } from "../../lib/csp.js";
 import { formatZodErrors } from "../../lib/errors.js";
 import { sanitizeFilename } from "../../lib/filename.js";
 
@@ -72,6 +73,7 @@ export function registerBulkRename(app: FastifyInstance) {
         "Content-Type": "application/zip",
         "Content-Disposition": `attachment; filename="renamed-${jobId.slice(0, 8)}.zip"`,
         "Transfer-Encoding": "chunked",
+        ...getSecurityHeaders(),
       });
 
       const archive = archiver("zip", { zlib: { level: 5 } });

apps/api/src/routes/tools/favicon.ts

@@ -4,6 +4,7 @@ import type { FastifyInstance } from "fastify";
 import sharp from "sharp";
 import { z } from "zod";
 import { autoOrient } from "../../lib/auto-orient.js";
+import { getSecurityHeaders } from "../../lib/csp.js";
 import { formatZodErrors } from "../../lib/errors.js";
 import { validateImageBuffer } from "../../lib/file-validation.js";
 import { sanitizeFilename } from "../../lib/filename.js";
@@ -146,6 +147,7 @@ export function registerFavicon(app: FastifyInstance) {
         "Content-Type": "application/zip",
         "Content-Disposition": `attachment; filename="favicons-${jobId.slice(0, 8)}.zip"`,
         "Transfer-Encoding": "chunked",
+        ...getSecurityHeaders(),
       });
 
       const archive = archiver("zip", { zlib: { level: 5 } });

apps/api/src/routes/tools/ocr.ts

@@ -57,7 +57,10 @@ export function registerOcr(app: FastifyInstance) {
         } else if (part.fieldname === "settings") {
           settingsRaw = part.value as string;
         } else if (part.fieldname === "clientJobId") {
-          clientJobId = part.value as string;
+          const raw = part.value as string;
+          if (typeof raw === "string" && raw.length > 0 && raw.length <= 128) {
+            clientJobId = raw;
+          }
         }
       }
     } catch (err) {

apps/api/src/routes/tools/passport-photo.ts

@@ -157,7 +157,10 @@ export function registerPassportPhoto(app: FastifyInstance) {
             fileBuffer = Buffer.concat(chunks);
             filename = sanitizeFilename(part.filename ?? "image");
           } else if (part.fieldname === "clientJobId") {
-            clientJobId = part.value as string;
+            const raw = part.value as string;
+            if (typeof raw === "string" && raw.length > 0 && raw.length <= 128) {
+              clientJobId = raw;
+            }
           }
         }
       } catch (err) {

apps/api/src/routes/tools/split.ts

@@ -5,6 +5,7 @@ import type { FastifyInstance } from "fastify";
 import sharp from "sharp";
 import { z } from "zod";
 import { autoOrient } from "../../lib/auto-orient.js";
+import { getSecurityHeaders } from "../../lib/csp.js";
 import { formatZodErrors } from "../../lib/errors.js";
 import { validateImageBuffer } from "../../lib/file-validation.js";
 import { sanitizeFilename } from "../../lib/filename.js";
@@ -162,6 +163,7 @@ export function registerSplit(app: FastifyInstance) {
         "Content-Type": "application/zip",
         "Content-Disposition": `attachment; filename="split-${jobId.slice(0, 8)}.zip"`,
         "Transfer-Encoding": "chunked",
+        ...getSecurityHeaders(),
       });
 
       const archive = archiver("zip", { zlib: { level: 5 } });

apps/api/src/routes/tools/svg-to-raster.ts

@@ -7,6 +7,7 @@ import PQueue from "p-queue";
 import sharp from "sharp";
 import { z } from "zod";
 import { env } from "../../config.js";
+import { getSecurityHeaders } from "../../lib/csp.js";
 import { resolveConcurrency } from "../../lib/env.js";
 import { formatZodErrors } from "../../lib/errors.js";
 import { sanitizeFilename } from "../../lib/filename.js";
@@ -129,7 +130,10 @@ export function registerSvgToRaster(app: FastifyInstance) {
         } else if (part.fieldname === "settings") {
           settingsRaw = part.value as string;
         } else if (part.fieldname === "clientJobId") {
-          clientJobId = part.value as string;
+          const raw = part.value as string;
+          if (typeof raw === "string" && raw.length > 0 && raw.length <= 128) {
+            clientJobId = raw;
+          }
         }
       }
     } catch (err) {
@@ -321,6 +325,7 @@ export function registerSvgToRaster(app: FastifyInstance) {
       "Transfer-Encoding": "chunked",
       "X-Job-Id": jobId,
       "X-File-Results": encodeURIComponent(JSON.stringify(fileResultsMap)),
+      ...getSecurityHeaders(),
     });
 
     const archive = archiver("zip", { zlib: { level: 5 } });