diff --git a/packages/cactus-plugin-ledger-connector-ethereum/package.json b/packages/cactus-plugin-ledger-connector-ethereum/package.json
index 21c835ccad..7eef38e4f8 100644
--- a/packages/cactus-plugin-ledger-connector-ethereum/package.json
+++ b/packages/cactus-plugin-ledger-connector-ethereum/package.json
@@ -65,11 +65,13 @@
     "webpack:dev:web": "webpack --env=dev --target=web --config ../../webpack.config.js"
   },
   "dependencies": {
+    "@apidevtools/json-schema-ref-parser": "12.0.1",
     "@ethereumjs/common": "4.0.0",
     "@ethereumjs/tx": "5.0.0",
     "@hyperledger/cactus-common": "2.1.0",
     "@hyperledger/cactus-core": "2.1.0",
     "@hyperledger/cactus-core-api": "2.1.0",
+    "ajv": "8.17.1",
     "axios": "1.8.4",
     "ethers": "6.8.1",
     "express": "5.1.0",
diff --git a/packages/cactus-plugin-ledger-connector-ethereum/src/main/typescript/web-services/deploy-contract-v1-endpoint.ts b/packages/cactus-plugin-ledger-connector-ethereum/src/main/typescript/web-services/deploy-contract-v1-endpoint.ts
index b05396bdac..38e02412fa 100644
--- a/packages/cactus-plugin-ledger-connector-ethereum/src/main/typescript/web-services/deploy-contract-v1-endpoint.ts
+++ b/packages/cactus-plugin-ledger-connector-ethereum/src/main/typescript/web-services/deploy-contract-v1-endpoint.ts
@@ -1,4 +1,6 @@
 import { Express, Request, Response } from "express";
+import { Ajv } from "ajv";
+import RefParser from "@apidevtools/json-schema-ref-parser";
 
 import {
   IWebServiceEndpoint,
@@ -22,6 +24,53 @@ import OAS from "../../json/openapi.json";
 import { ERR_INVALID_RESPONSE } from "web3";
 import { isWeb3Error } from "../public-api";
 
+async function preprocessSchema() {
+  const resolvedSchema = await RefParser.dereference(OAS);
+  function adjustNullable(obj: Record<string, unknown>) {
+    if (typeof obj !== "object" || obj === null) return;
+    if ("nullable" in obj && !("type" in obj)) {
+      delete obj.nullable;
+    }
+    if (obj.nullable === true && obj.type && typeof obj.type === "string") {
+      obj.type = [obj.type, "null"];
+      delete obj.nullable;
+    }
+    if (obj.nullable === false) {
+      delete obj.nullable;
+    }
+    for (const key in obj) {
+      if (typeof obj[key] === "object" && obj[key] !== null) {
+        adjustNullable(obj[key] as Record<string, unknown>);
+      }
+    }
+  }
+
+  adjustNullable(resolvedSchema as Record<string, unknown>);
+  return resolvedSchema;
+}
+
+let validateDeployContract: ReturnType<Ajv["compile"]> | undefined;
+async function getValidateDeployContract(): Promise<
+  ReturnType<Ajv["compile"]>
+> {
+  if (validateDeployContract) {
+    return validateDeployContract;
+  }
+
+  const ajv = new Ajv({
+    allErrors: true,
+    strict: false,
+    allowMatchingProperties: true,
+  });
+  const processedSchema = await preprocessSchema();
+  ajv.addSchema(processedSchema, "openapi.json");
+
+  validateDeployContract = ajv.compile({
+    $ref: "openapi.json#/components/schemas/DeployContractV1Request",
+  });
+  return validateDeployContract;
+}
+
 export interface IDeployContractSolidityBytecodeOptions {
   logLevel?: LogLevelDesc;
   connector: PluginLedgerConnectorEthereum;
@@ -88,6 +137,18 @@ export class DeployContractEndpoint implements IWebServiceEndpoint {
   public async handleRequest(req: Request, res: Response): Promise<void> {
     const reqTag = `${this.getVerbLowerCase()} - ${this.getPath()}`;
     this.log.debug(reqTag);
+
+    const validate = await getValidateDeployContract();
+    const isValid = validate(req.body);
+    if (!isValid) {
+      const errorDetails = JSON.stringify(validate.errors);
+      this.log.debug(`Validation failed for ${reqTag}: ${errorDetails}`);
+      res.status(400).json({
+        message: "Invalid request body",
+        errors: validate.errors,
+      });
+      return;
+    }
     try {
       res
         .status(200)
diff --git a/packages/cactus-plugin-ledger-connector-ethereum/src/test/typescript/integration/geth-contract-deploy-and-invoke-using-json-object-v1.test.ts b/packages/cactus-plugin-ledger-connector-ethereum/src/test/typescript/integration/geth-contract-deploy-and-invoke-using-json-object-v1.test.ts
index 8c6815ad9a..c78f5a2a4e 100644
--- a/packages/cactus-plugin-ledger-connector-ethereum/src/test/typescript/integration/geth-contract-deploy-and-invoke-using-json-object-v1.test.ts
+++ b/packages/cactus-plugin-ledger-connector-ethereum/src/test/typescript/integration/geth-contract-deploy-and-invoke-using-json-object-v1.test.ts
@@ -243,8 +243,8 @@ describe("Ethereum contract deploy and invoke using keychain tests", () => {
   });
 
   test("deployContract with additional parameters should fail", async () => {
-    try {
-      await apiClient.deployContract({
+    await expect(
+      apiClient.deployContract({
         contract: {
           contractJSON: HelloWorldContractJson,
         },
@@ -255,11 +255,15 @@ describe("Ethereum contract deploy and invoke using keychain tests", () => {
         },
         gas: 1000000,
         fake: 4,
-      } as DeployContractV1Request);
-      fail("Expected deployContract call to fail but it succeeded.");
-    } catch (error) {
-      console.log("deployContract failed as expected");
-    }
+      } as DeployContractV1Request),
+    ).rejects.toMatchObject({
+      response: {
+        status: 400,
+        data: {
+          message: expect.stringContaining("Invalid request body"),
+        },
+      },
+    });
   });
 
   //////////////////////////////////
diff --git a/yarn.lock b/yarn.lock
index 5945bb18e2..133fcbc818 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -805,6 +805,17 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@apidevtools/json-schema-ref-parser@npm:12.0.1":
+  version: 12.0.1
+  resolution: "@apidevtools/json-schema-ref-parser@npm:12.0.1"
+  dependencies:
+    "@jsdevtools/ono": "npm:^7.1.3"
+    "@types/json-schema": "npm:^7.0.15"
+    js-yaml: "npm:^4.1.0"
+  checksum: 10/1ebe4b623dc841ac7137abb68e573a91350fcca38185379da52e1ab888fcb4cf706026bc41436dbb61a82ca830c8221e04b8432252bbb34815cfee5f290d0a22
+  languageName: node
+  linkType: hard
+
 "@apidevtools/json-schema-ref-parser@npm:^11.6.2":
   version: 11.6.4
   resolution: "@apidevtools/json-schema-ref-parser@npm:11.6.4"
@@ -10616,6 +10627,7 @@ __metadata:
   version: 0.0.0-use.local
   resolution: "@hyperledger/cactus-plugin-ledger-connector-ethereum@workspace:packages/cactus-plugin-ledger-connector-ethereum"
   dependencies:
+    "@apidevtools/json-schema-ref-parser": "npm:12.0.1"
     "@ethereumjs/common": "npm:4.0.0"
     "@ethereumjs/tx": "npm:5.0.0"
     "@hyperledger/cactus-common": "npm:2.1.0"
@@ -10630,6 +10642,7 @@ __metadata:
     "@types/minimist": "npm:1.2.2"
     "@types/sanitize-html": "npm:2.9.5"
     "@types/uuid": "npm:10.0.0"
+    ajv: "npm:8.17.1"
     axios: "npm:1.8.4"
     body-parser: "npm:1.20.3"
     chalk: "npm:4.1.2"