diff --git a/backend/routes.js b/backend/routes.js
index 80476a344d..e255760078 100644
--- a/backend/routes.js
+++ b/backend/routes.js
@@ -821,7 +821,7 @@ route.GET('/zkpp/{name}/contract_hash', {
   return Boom.internal('internal error')
 })
 
-route.POST('/zkpp/updatePasswordHash/{name}', {
+route.POST('/zkpp/{name}/updatePasswordHash', {
   validate: {
     payload: Joi.object({
       r: Joi.string().required(),
@@ -841,7 +841,7 @@ route.POST('/zkpp/updatePasswordHash/{name}', {
     }
   } catch (e) {
     e.ip = req.headers['x-real-ip'] || req.info.remoteAddress
-    console.error(e, 'Error at POST /zkpp/updatePasswordHash/{name}: ' + e.message)
+    console.error(e, 'Error at POST /zkpp/{name}/updatePasswordHash: ' + e.message)
   }
 
   return Boom.internal('internal error')
diff --git a/frontend/controller/app/identity.js b/frontend/controller/app/identity.js
index 6d2ede4a80..064455028c 100644
--- a/frontend/controller/app/identity.js
+++ b/frontend/controller/app/identity.js
@@ -6,7 +6,7 @@ import sbp from '@sbp/sbp'
 import Vue from 'vue'
 import { LOGIN, LOGIN_COMPLETE, LOGIN_ERROR } from '~/frontend/utils/events.js'
 import { Secret } from '~/shared/domains/chelonia/Secret.js'
-import { boxKeyPair, buildRegisterSaltRequest, computeCAndHc, decryptContractSalt, hash, hashPassword, randomNonce } from '~/shared/zkpp.js'
+import { boxKeyPair, buildRegisterSaltRequest, buildUpdateSaltRequestEa, computeCAndHc, decryptContractSalt, hash, hashPassword, randomNonce } from '~/shared/zkpp.js'
 // Using relative path to crypto.js instead of ~-path to workaround some esbuild bug
 import { CURVE25519XSALSA20POLY1305, EDWARDS25519SHA512BATCH, deriveKeyFromPassword, serializeKey } from '../../../shared/domains/chelonia/crypto.js'
 import { handleFetchResult } from '../utils/misc.js'
@@ -177,6 +177,37 @@ export default (sbp('sbp/selectors/register', {
 
     return decryptContractSalt(c, contractHash)
   },
+  'gi.app/identity/updateSalt': async (username: string, oldPassword: Secret<string>, newPassword: Secret<string>) => {
+    const r = randomNonce()
+    const b = hash(r)
+    const authHash = await fetch(`${sbp('okTurtles.data/get', 'API_URL')}/zkpp/${encodeURIComponent(username)}/auth_hash?b=${encodeURIComponent(b)}`)
+      .then(handleFetchResult('json'))
+
+    const { authSalt, s, sig } = authHash
+
+    const h = await hashPassword(oldPassword.valueOf(), authSalt)
+
+    const [c, hc] = computeCAndHc(r, s, h)
+
+    const [contractHash, encryptedArgs] = await buildUpdateSaltRequestEa(newPassword.valueOf(), c)
+
+    await fetch(`${sbp('okTurtles.data/get', 'API_URL')}/zkpp/${encodeURIComponent(username)}/updatePasswordHash`, {
+      method: 'POST',
+      headers: {
+        'content-type': 'application/x-www-form-urlencoded'
+      },
+      body:
+        `${(new URLSearchParams({
+          'r': r,
+          's': s,
+          'sig': sig,
+          'hc': Buffer.from(hc).toString('base64').replace(/\//g, '_').replace(/\+/g, '-').replace(/=*$/, ''),
+          'Ea': encryptedArgs.toString('base64').replace(/\//g, '_').replace(/\+/g, '-').replace(/=*$/, '')
+        })).toString()}`
+    }).then(handleFetchResult('text'))
+
+    return contractHash
+  },
   'gi.app/identity/create': async function ({
     data: { username, email, password, picture },
     publishOptions
@@ -409,5 +440,22 @@ export default (sbp('sbp/selectors/register', {
   },
   'gi.app/identity/logout': (...params) => {
     return sbp('okTurtles.eventQueue/queueEvent', 'APP-LOGIN', ['gi.app/identity/_private/logout', ...params])
+  },
+  'gi.app/identity/changePassword': async (woldPassword: Secret<string>, wnewPassword: Secret<string>) => {
+    const state = sbp('state/vuex/state')
+    if (!state.loggedIn) return
+    const getters = sbp('state/vuex/getters')
+
+    const { identityContractID } = state.loggedIn
+    const username = getters.usernameFromID(identityContractID)
+    // const oldPassword = woldPassword.valueOf()
+    // const newPassword = wnewPassword.valueOf()
+
+    const contractSalt = await sbp('gi.app/identity/updateSalt', username, woldPassword, wnewPassword)
+
+    return contractSalt
+
+    /* const IPK = await deriveKeyFromPassword(EDWARDS25519SHA512BATCH, newPassword, contractSalt)
+    const IEK = await deriveKeyFromPassword(CURVE25519XSALSA20POLY1305, newPassword, contractSalt) */
   }
 }): string[])
diff --git a/package-lock.json b/package-lock.json
index 666ba223a7..8b2b25b402 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "group-income",
-  "version": "1.0.7",
+  "version": "1.1.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "group-income",
-      "version": "1.0.7",
+      "version": "1.1.0",
       "license": "AGPL-3.0",
       "dependencies": {
         "@babel/core": "7.23.7",
diff --git a/shared/zkpp.js b/shared/zkpp.js
index 55ce56bf24..044d34c693 100644
--- a/shared/zkpp.js
+++ b/shared/zkpp.js
@@ -114,3 +114,29 @@ export const buildRegisterSaltRequest = async (publicKey: string, secretKey: Uin
 
   return [contractSalt, base64ToBase64url(Buffer.concat([nonce, encryptedHashedPasswordBuf]).toString('base64'))]
 }
+
+export const buildUpdateSaltRequestEa = async (password: string, c: Uint8Array): Promise<[string, string]> => {
+  // TODO: Derive S_A and S_C as follows:
+  //   -> q -< random
+  //   -> r -< SHA-512(SHA-512('SU') + SHA-512(q))
+  //   -> b -< SHA-512(r) // as it's now
+  // Then,
+  //   -> S_T -< BASE64(SHA-512(SHA-512(T) + SHA-512(q))[0..18]) with T being
+  //     `AUTHSALT` or `CONTRACTSALT`
+  // This way, we ensure both the server and the client contribute to the
+  //   salts' entropy.
+  // When sending the encrypted data, the encrypted information would be
+  // `[hashedPassword, q]`, which needs to be verified server-side to verify
+  // it matches p and would be used to derive S_A and S_C.
+  const [authSalt, contractSalt] = ['a', 'b']
+
+  const encryptionKey = nacl.hash(Buffer.concat([Buffer.from('SU'), c])).slice(0, nacl.secretbox.keyLength)
+  const nonce = nacl.randomBytes(nacl.secretbox.nonceLength)
+
+  const hashedPassword = await hashPassword(password, authSalt)
+  const encryptedArgsCiphertext = nacl.secretbox(Buffer.from(JSON.stringify([hashedPassword, authSalt, contractSalt])), nonce, encryptionKey)
+
+  const encryptedArgs = Buffer.concat([nonce, encryptedArgsCiphertext])
+
+  return [contractSalt, base64ToBase64url(encryptedArgs.toString('base64'))]
+}