diff --git a/src/mdoc/Verifier.ts b/src/mdoc/Verifier.ts
index 462b39f..8f1e59e 100644
--- a/src/mdoc/Verifier.ts
+++ b/src/mdoc/Verifier.ts
@@ -1,18 +1,20 @@
 import { compareVersions } from 'compare-versions';
 import { X509Certificate } from '@peculiar/x509';
-import { importX509, JWK, KeyLike } from 'jose';
+import { importJWK, importX509, JWK, KeyLike } from 'jose';
 import { Buffer } from 'buffer';
-import { COSEKeyToJWK, Sign1, importCOSEKey } from 'cose-kit';
+import { COSEKeyToJWK, Sign1 } from 'cose-kit';
 import crypto from 'uncrypto';
 import { MDoc } from './model/MDoc';
 
 import {
   calculateEphemeralMacKey,
   calculateDeviceAutenticationBytes,
+  getAlgFromCurve,
 } from './utils';
 
 import {
   DiagnosticInformation,
+  SupportedAlgs,
 } from './model/types';
 import { UserDefinedVerificationCallback, VerificationAssessment, buildCallback, onCatCheck } from './checkCallback';
 
@@ -29,6 +31,7 @@ const DIGEST_ALGS = {
   'SHA-512': 'sha512',
 } as { [key: string]: string };
 
+
 export class Verifier {
   /**
    *
@@ -147,10 +150,28 @@ export class Verifier {
     }
 
     if (deviceAuth.deviceSignature) {
-      const deviceKey = await importCOSEKey(deviceKeyCoseKey);
+      const deviceKeyJwk = COSEKeyToJWK(deviceKeyCoseKey);
+      
+      // Determine algorithm from curve according to ISO/IEC 18013-5
+      let alg: SupportedAlgs;
+      try {
+        alg = getAlgFromCurve(deviceKeyJwk.crv);
+        onCheck({
+          status: 'PASSED',
+          check: `Device key curve '${deviceKeyJwk.crv}' is supported`,
+        });
+      } catch (err) {
+        onCheck({
+          status: 'FAILED',
+          check: 'Device key must use a supported curve',
+          reason: err.message,
+        });
+        return;
+      }
 
       // ECDSA/EdDSA authentication
       try {
+        const deviceKey = await importJWK(deviceKeyJwk, alg);
         const ds = deviceAuth.deviceSignature;
 
         const verificationResult = await new Sign1(
diff --git a/src/mdoc/utils.ts b/src/mdoc/utils.ts
index cf395f0..6b7c3c8 100644
--- a/src/mdoc/utils.ts
+++ b/src/mdoc/utils.ts
@@ -10,6 +10,7 @@ import { COSEKeyToJWK } from 'cose-kit';
 import { cborEncode, cborDecode } from '../cbor';
 import { DataItem } from '../cbor/DataItem';
 import COSEKeyToRAW from '../cose/coseKey';
+import { SupportedAlgs } from './model/types';
 
 const { subtle } = webcrypto;
 
@@ -124,3 +125,42 @@ export function fromPEM(pem: string): Uint8Array {
   const base64 = pem.replace(/-{5}(BEGIN|END) .*-{5}/gm, '').replace(/\s/gm, '');
   return Buffer.from(base64, 'base64');
 }
+
+/**
+ * Maps elliptic curve identifiers to signature algorithms according to ISO/IEC 18013-5.
+ * 
+ * - ES256 (ECDSA with SHA-256): P-256, brainpoolP256r1
+ * - ES384 (ECDSA with SHA-384): P-384, brainpoolP320r1, brainpoolP384r1
+ * - ES512 (ECDSA with SHA-512): P-521, brainpoolP512r1
+ * - EdDSA: Ed25519, Ed448
+ */
+const CURVE_TO_ALG: Record<string, SupportedAlgs> = {
+  'P-256': 'ES256',
+  'brainpoolP256r1': 'ES256',
+  'P-384': 'ES384',
+  'brainpoolP320r1': 'ES384',
+  'brainpoolP384r1': 'ES384',
+  'P-521': 'ES512',
+  'brainpoolP512r1': 'ES512',
+  'Ed25519': 'EdDSA',
+  'Ed448': 'EdDSA',
+} as const;
+
+/**
+ * Determines the signature algorithm based on the JWK curve parameter.
+ * 
+ * @param crv - The curve identifier from the JWK
+ * @returns The corresponding signature algorithm
+ * @throws Error if the curve is not supported
+ */
+export function getAlgFromCurve(crv: string | undefined): SupportedAlgs {
+  if (!crv) {
+    throw new Error('Missing curve (crv) parameter in device key');
+  }
+  const alg = CURVE_TO_ALG[crv as keyof typeof CURVE_TO_ALG];
+  if (!alg) {
+    throw new Error(`Unsupported curve: ${crv}`);
+  }
+  return alg;
+}
+