diff --git a/lib/config/__fixtures__/private.pem b/lib/config/__fixtures__/private.pem
deleted file mode 100644
index efee57e904..0000000000
--- a/lib/config/__fixtures__/private.pem
+++ /dev/null
@@ -1,27 +0,0 @@
------BEGIN RSA PRIVATE KEY-----
-MIIEpQIBAAKCAQEAzVLc1KmhWxcLnoPTPpQwxVHySFx4vY+0Sk+2AdnlJvrTFlNR
-8XgBPdgU9SDwHFFTYyXRQ/msm0YMOBRoIdz4/psz6IzRV80aOtDIkUPAU+cdqnje
-3rusrPnqCykDuIHGoBZ8zlt57t/8OVNOduUflrQRqMFors8iLWcNjuGJfZAusI5B
-M8KYYDPL2oUo/8AV0bWN8MdNnxDSwGtan4bbzrtG6dpNzyntsG5DkL1h8OZRki4S
-kHf+71ZzJFz1KcyrzBVJ9DBxdiJdmLLkv9caLLc2QS0VFmtfLnlrga3Sahy6YNwc
-rN33aaNOXwFPSErsKWIgIf16eOaSUQCFusXY9QIDAQABAoIBAQCkltMM6nm9Ikkf
-JX9V/8bkth7o4K+tDSAyHZnB/CBUUeaaU+oxDci5AZkzMtcnbA3TQcJxohg6VDmB
-TuJ2msNCnblLpm492t023pyYzd3DpFXEjKXjmEAAXUm+7n7cDbPiKoSbivrAgO6Y
-KW6RonPjA6/QPlIjJ0m3aY+VxLfJXTYVfFBk+0HGEAvmrSSSEezXej8Qzs9CRKtz
-cQkR5Bs749SS509MHxaslP7n366EvJBJkqrjUxA6kbxOxUkuuOWF9jfduDAG+NYc
-pe4IXFOYMpK/w29wqvkNulKYs+FHXr1sGjkztGjyNnjP0NnX+r0EYU07xLJ26krD
-KMWQG8sBAoGBAO93iFrPnEBnnKojI8b+u3YowVCz0HVuHHIStHd9uUgfsn/Bxfls
-HRIlg8l1MJd69TT0knOhkJxBCP+b/qBvid7YLbTxIVELCAfLAzsmGgY+DEN/TTUb
-FDvHGa/drCnkSR/O/RbtHvMQISzTja1siYrdwwY+wpwzR2tB7ZH/9iO1AoGBANt/
-3Srpv4BbP7JZ+cNte4JfI2gZq41mo+DF5ryuFZzsP3R5SZ1BOapQGyLEATQaoxsJ
-QZsI73KPBzab0/+E75qJuXckIGmFftHXgoQpClGvPaEDF9M21QW5Y3vKVa/45qhy
-3wpb8gEYqrt1x0rmzyumCtCD8J470Er64gE1eKhBAoGBALW6ScFYwqRhvROkvTb8
-A7mE7kfXXgBwAqhTJ59yytRAMc8gd6R0do9Z5uxQwgKDLmj0ndugpcTe2fxZHuAU
-JVX3SqCBSZ5eN8bqOtZ9cMyB8/6ZMjd2CGHhE85R9KCJ/TBlfc4TPySIfhStq1wL
-/UlkR+eKY1f01mNAUhE1ZU7tAoGBAKwS/B51KsSERFYcRToYbRfSX55vaVarnVNL
-scw+qQDhEAnOP5CBHqTOscc6YzsmmrFKO10/zv8+80ezN6n73B6JU5T8BFDU74uv
-6EiVJ9rLh4PfOeFB/hPDtyLHhw8yEBkEHKgxVnHXlZjqBzdH5Cdyvs2icZKKj4sI
-TP7nnVRBAoGAPZBjjTn9HgB9et5Kdovp+7nr842WboxwklVyTpbNGAjIxNXIXex+
-TST21UbquTIpIrpYRk1WMIu9T5PndAagDWVEsmUYQZeuhmuY64K+iviRsfdGthws
-nbbR8sMEkn4XEtPZfrEBq27g01RNmIIMW5Es2O5N2AjLlyeBOh099Fw=
------END RSA PRIVATE KEY-----
diff --git a/lib/config/decrypt.ts b/lib/config/decrypt.ts
index 5920c0e879..729e7015e4 100644
--- a/lib/config/decrypt.ts
+++ b/lib/config/decrypt.ts
@@ -6,10 +6,6 @@ import { regEx } from '../util/regex';
 import { addSecretForSanitizing } from '../util/sanitize';
 import { ensureTrailingSlash, parseUrl, trimSlashes } from '../util/url';
 import { tryDecryptKbPgp } from './decrypt/kbpgp';
-import {
-  tryDecryptPublicKeyDefault,
-  tryDecryptPublicKeyPKCS1,
-} from './decrypt/legacy';
 import { tryDecryptOpenPgp } from './decrypt/openpgp';
 import { GlobalConfig } from './global';
 import { DecryptedObject } from './schema';
@@ -30,35 +26,14 @@ export async function tryDecrypt(
   key: string,
   encryptedStr: string,
   repository: string,
-  keyName: string,
 ): Promise<string | null> {
   let decryptedStr: string | null = null;
-  if (key?.startsWith('-----BEGIN PGP PRIVATE KEY BLOCK-----')) {
-    const decryptedObjStr =
-      getEnv().RENOVATE_X_USE_OPENPGP === 'true'
-        ? await tryDecryptOpenPgp(key, encryptedStr)
-        : await tryDecryptKbPgp(key, encryptedStr);
-    if (decryptedObjStr) {
-      decryptedStr = validateDecryptedValue(decryptedObjStr, repository);
-    }
-  } else {
-    decryptedStr = tryDecryptPublicKeyDefault(key, encryptedStr);
-    if (is.string(decryptedStr)) {
-      logger.warn(
-        { keyName },
-        'Encrypted value is using deprecated default padding, please change to using PGP encryption.',
-      );
-    } else {
-      decryptedStr = tryDecryptPublicKeyPKCS1(key, encryptedStr);
-      /* v8 ignore start -- not testable */
-      if (is.string(decryptedStr)) {
-        logger.warn(
-          { keyName },
-          'Encrypted value is using deprecated PKCS1 padding, please change to using PGP encryption.',
-        );
-      }
-      /* v8 ignore stop */
-    }
+  const decryptedObjStr =
+    getEnv().RENOVATE_X_USE_OPENPGP === 'true'
+      ? await tryDecryptOpenPgp(key, encryptedStr)
+      : await tryDecryptKbPgp(key, encryptedStr);
+  if (decryptedObjStr) {
+    decryptedStr = validateDecryptedValue(decryptedObjStr, repository);
   }
   return decryptedStr;
 }
@@ -170,20 +145,10 @@ export async function decryptConfig(
       if (privateKey) {
         for (const [eKey, eVal] of Object.entries(val)) {
           logger.debug(`Trying to decrypt ${eKey} in ${path}`);
-          let decryptedStr = await tryDecrypt(
-            privateKey,
-            eVal,
-            repository,
-            eKey,
-          );
+          let decryptedStr = await tryDecrypt(privateKey, eVal, repository);
           if (privateKeyOld && !is.nonEmptyString(decryptedStr)) {
             logger.debug(`Trying to decrypt with old private key`);
-            decryptedStr = await tryDecrypt(
-              privateKeyOld,
-              eVal,
-              repository,
-              eKey,
-            );
+            decryptedStr = await tryDecrypt(privateKeyOld, eVal, repository);
           }
           if (!is.nonEmptyString(decryptedStr)) {
             const error = new Error('config-validation');
diff --git a/lib/config/decrypt/legacy.spec.ts b/lib/config/decrypt/legacy.spec.ts
deleted file mode 100644
index c28b80ca6f..0000000000
--- a/lib/config/decrypt/legacy.spec.ts
+++ /dev/null
@@ -1,88 +0,0 @@
-import { CONFIG_VALIDATION } from '../../constants/error-messages';
-import { decryptConfig, setPrivateKeys } from '../decrypt';
-import { GlobalConfig } from '../global';
-import type { RenovateConfig } from '../types';
-import { Fixtures } from '~test/fixtures';
-
-const privateKey = Fixtures.get('private.pem', '..');
-const repository = 'abc/def';
-
-describe('config/decrypt/legacy', () => {
-  describe('decryptConfig()', () => {
-    let config: RenovateConfig;
-
-    beforeEach(() => {
-      config = {};
-      GlobalConfig.reset();
-      setPrivateKeys(undefined, undefined);
-    });
-
-    it('handles invalid encrypted type', async () => {
-      config.encrypted = 1;
-      setPrivateKeys(privateKey, undefined);
-      const res = await decryptConfig(config, repository);
-      expect(res.encrypted).toBeUndefined();
-    });
-
-    it('handles invalid encrypted value', async () => {
-      config.encrypted = { a: 1 };
-      setPrivateKeys(privateKey, 'invalid-key');
-      await expect(decryptConfig(config, repository)).rejects.toThrow(
-        CONFIG_VALIDATION,
-      );
-    });
-
-    it('replaces npm token placeholder in npmrc', async () => {
-      setPrivateKeys('invalid-key', privateKey); // test old key failover
-      config.npmrc =
-        '//registry.npmjs.org/:_authToken=${NPM_TOKEN}\n//registry.npmjs.org/:_authToken=${NPM_TOKEN}\n';
-      config.encrypted = {
-        npmToken:
-          'FLA9YHIzpE7YetAg/P0X46npGRCMqn7hgyzwX5ZQ9wYgu9BRRbTiBVsUIFTyM5BuP1Q22slT2GkWvFvum7GU236Y6QiT7Nr8SLvtsJn2XUuq8H7REFKzdy3+wqyyWbCErYTFyY1dcPM7Ht+CaGDWdd8u/FsoX7AdMRs/X1jNUo6iSmlUiyGlYDKF+QMnCJom1VPVgZXWsGKdjI2MLny991QMaiv0VajmFIh4ENv4CtXOl/1twvIl/6XTXAaqpJJKDTPZEuydi+PHDZmal2RAOfrkH4m0UURa7SlfpUlIg+EaqbNGp85hCYXLwRcEET1OnYr3rH1oYkcYJ40any1tvQ==',
-      };
-      const res = await decryptConfig(config, repository);
-      expect(res.encrypted).toBeUndefined();
-      expect(res.npmToken).toBe('abcdef-ghijklm-nopqf-stuvwxyz');
-    });
-
-    it('appends npm token in npmrc', async () => {
-      setPrivateKeys(privateKey, undefined);
-      config.npmrc = 'foo=bar\n';
-      config.encrypted = {
-        npmToken:
-          'FLA9YHIzpE7YetAg/P0X46npGRCMqn7hgyzwX5ZQ9wYgu9BRRbTiBVsUIFTyM5BuP1Q22slT2GkWvFvum7GU236Y6QiT7Nr8SLvtsJn2XUuq8H7REFKzdy3+wqyyWbCErYTFyY1dcPM7Ht+CaGDWdd8u/FsoX7AdMRs/X1jNUo6iSmlUiyGlYDKF+QMnCJom1VPVgZXWsGKdjI2MLny991QMaiv0VajmFIh4ENv4CtXOl/1twvIl/6XTXAaqpJJKDTPZEuydi+PHDZmal2RAOfrkH4m0UURa7SlfpUlIg+EaqbNGp85hCYXLwRcEET1OnYr3rH1oYkcYJ40any1tvQ==',
-      };
-      const res = await decryptConfig(config, repository);
-      expect(res.encrypted).toBeUndefined();
-      expect(res.npmToken).toBe('abcdef-ghijklm-nopqf-stuvwxyz');
-    });
-
-    it('decrypts nested', async () => {
-      setPrivateKeys(privateKey, undefined);
-      config.packageFiles = [
-        {
-          packageFile: 'package.json',
-          devDependencies: {
-            encrypted: {
-              branchPrefix:
-                'FLA9YHIzpE7YetAg/P0X46npGRCMqn7hgyzwX5ZQ9wYgu9BRRbTiBVsUIFTyM5BuP1Q22slT2GkWvFvum7GU236Y6QiT7Nr8SLvtsJn2XUuq8H7REFKzdy3+wqyyWbCErYTFyY1dcPM7Ht+CaGDWdd8u/FsoX7AdMRs/X1jNUo6iSmlUiyGlYDKF+QMnCJom1VPVgZXWsGKdjI2MLny991QMaiv0VajmFIh4ENv4CtXOl/1twvIl/6XTXAaqpJJKDTPZEuydi+PHDZmal2RAOfrkH4m0UURa7SlfpUlIg+EaqbNGp85hCYXLwRcEET1OnYr3rH1oYkcYJ40any1tvQ==',
-              npmToken:
-                'FLA9YHIzpE7YetAg/P0X46npGRCMqn7hgyzwX5ZQ9wYgu9BRRbTiBVsUIFTyM5BuP1Q22slT2GkWvFvum7GU236Y6QiT7Nr8SLvtsJn2XUuq8H7REFKzdy3+wqyyWbCErYTFyY1dcPM7Ht+CaGDWdd8u/FsoX7AdMRs/X1jNUo6iSmlUiyGlYDKF+QMnCJom1VPVgZXWsGKdjI2MLny991QMaiv0VajmFIh4ENv4CtXOl/1twvIl/6XTXAaqpJJKDTPZEuydi+PHDZmal2RAOfrkH4m0UURa7SlfpUlIg+EaqbNGp85hCYXLwRcEET1OnYr3rH1oYkcYJ40any1tvQ==',
-            },
-          },
-        },
-        'backend/package.json',
-      ];
-      // TODO: fix types #22198
-      const res = (await decryptConfig(config, repository)) as any;
-      expect(res.encrypted).toBeUndefined();
-      expect(res.packageFiles[0].devDependencies.encrypted).toBeUndefined();
-      expect(res.packageFiles[0].devDependencies.branchPrefix).toBe(
-        'abcdef-ghijklm-nopqf-stuvwxyz',
-      );
-      expect(res.packageFiles[0].devDependencies.npmToken).toBe(
-        'abcdef-ghijklm-nopqf-stuvwxyz',
-      );
-    });
-  });
-});
diff --git a/lib/config/decrypt/legacy.ts b/lib/config/decrypt/legacy.ts
deleted file mode 100644
index c220bb3ca9..0000000000
--- a/lib/config/decrypt/legacy.ts
+++ /dev/null
@@ -1,39 +0,0 @@
-import crypto from 'node:crypto';
-import { logger } from '../../logger';
-
-export function tryDecryptPublicKeyPKCS1(
-  privateKey: string,
-  encryptedStr: string,
-): string | null {
-  let decryptedStr: string | null = null;
-  try {
-    decryptedStr = crypto
-      .privateDecrypt(
-        {
-          key: privateKey,
-          padding: crypto.constants.RSA_PKCS1_PADDING,
-        },
-        Buffer.from(encryptedStr, 'base64'),
-      )
-      .toString();
-  } catch {
-    logger.debug('Could not decrypt using PKCS1 padding');
-  }
-  return decryptedStr;
-}
-
-export function tryDecryptPublicKeyDefault(
-  privateKey: string,
-  encryptedStr: string,
-): string | null {
-  let decryptedStr: string | null = null;
-  try {
-    decryptedStr = crypto
-      .privateDecrypt(privateKey, Buffer.from(encryptedStr, 'base64'))
-      .toString();
-    logger.debug('Decrypted config using default padding');
-  } catch {
-    logger.debug('Could not decrypt using default padding');
-  }
-  return decryptedStr;
-}