New Challenge - Vault Template Injection

.github/scripts/.bash_history

@@ -347,7 +347,7 @@ rm -rf jdk-18_linux-x64_bin.deb
 git rebase -i main
 git rebase -i master
 git stash
-export tempPassword="1f94QXGi8zGUNiT91bconrnPLl44bCY59Y8itGyN6Yg="
+export tempPassword="dWTZkr5BPvnJYw+8sXtwQX8bCVTtsCrAL//mgrzeYTY="
 mvn run tempPassword
 k6
 npx k6

k8s-vault-minkube-start.sh

@@ -81,6 +81,9 @@ kubectl exec vault-0 -n vault -- vault secrets enable -path=secret kv-v2
 echo "Putting a secret in"
 kubectl exec vault-0 -n vault -- vault kv put secret/secret-challenge vaultpassword.password="$(openssl rand -base64 16)"
 
+echo "Putting a challenge key in"
+kubectl exec vault-0 -n vault -- vault kv put secret/injected vaultinjected.value="$(openssl rand -base64 16)"
+
 echo "Putting a subkey issue in"
 kubectl exec vault-0 -n vault -- vault kv put secret/wrongsecret aaaauser."$(openssl rand -base64 8)"="$(openssl rand -base64 16)"
 
@@ -115,6 +118,9 @@ path "secret/data/wrongsecret" {
 path "secret/data/application" {
   capabilities = ["read"]
 }
+path "secret/data/injected" {
+  capabilities = ["read"]
+}
 EOF'
 
 kubectl exec vault-0 -n vault -- /bin/sh -c 'vault policy write standard_sre - <<EOF

k8s/helm-vault-values.yml

@@ -2,3 +2,6 @@ server:
   affinity:
   ha:
     enabled: true
+
+injector:
+  enabled: true

k8s/secret-challenge-vault-deployment.yml

@@ -19,6 +19,20 @@ spec:
     type: RollingUpdate
   template:
     metadata:
+      annotations:
+        vault.hashicorp.com/agent-inject: "true"
+        vault.hashicorp.com/tls-skip-verify: 'true'
+        vault.hashicorp.com/agent-inject-status: "update"
+        vault.hashicorp.com/namespace: "default"
+        vault.hashicorp.com/log-level: debug
+        vault.hashicorp.com/agent-inject-secret-challenge46: "secret/data/injected"
+        vault.hashicorp.com/agent-inject-template-challenge46: |
+          {{ with secret "/secret/data/injected" }}
+            {{ range $k, $v := .Data.data }}
+              {{ printf "%s=%s" $k $v }}
+            {{ end }}
+          {{ end }}
+        vault.hashicorp.com/role: "secret-challenge"
       labels:
         app: secret-challenge
       name: secret-challenge
@@ -28,9 +42,11 @@ spec:
         fsGroup: 2000
         runAsGroup: 2000
         runAsNonRoot: true
+        seccompProfile:
+          type: RuntimeDefault
       serviceAccountName: vault
       containers:
-        - image: jeroenwillemsen/wrongsecrets:1.8.2-k8s-vault
+        - image: jeroenwillemsen/wrongsecrets:vaultinjection-2-test-k8s-vault
           imagePullPolicy: IfNotPresent
           name: secret-challenge
           securityContext:

scripts/install-vault.sh

@@ -49,6 +49,9 @@ kubectl exec vault-0 -n vault -- vault secrets enable -path=secret kv-v2
 echo "Putting a secret in"
 kubectl exec vault-0 -n vault -- vault kv put secret/secret-challenge vaultpassword.password="$(openssl rand -base64 16)"
 
+echo "Putting a challenge key in"
+kubectl exec vault-0 -n vault -- vault kv put secret/injected vaultinjected.value="$(openssl rand -base64 16)"
+
 echo "Putting a subkey issue in"
 kubectl exec vault-0 -n vault -- vault kv put secret/wrongsecret aaaauser."$(openssl rand -base64 8)"="$(openssl rand -base64 16)"
 
@@ -81,6 +84,9 @@ path "secret/data/wrongsecret" {
 path "secret/data/application" {
   capabilities = ["read"]
 }
+path "secret/data/injected" {
+  capabilities = ["read"]
+}
 EOF'
 
 kubectl exec vault-0 -n vault -- /bin/sh -c 'vault policy write standard_sre - <<EOF

src/main/java/org/owasp/wrongsecrets/WrongSecretsApplication.java

@@ -1,5 +1,6 @@
 package org.owasp.wrongsecrets;
 
+import org.owasp.wrongsecrets.challenges.kubernetes.Vaultinjected;
 import org.owasp.wrongsecrets.challenges.kubernetes.Vaultpassword;
 import org.owasp.wrongsecrets.definitions.ChallengeDefinitionsConfiguration;
 import org.springframework.beans.factory.annotation.Value;
@@ -11,7 +12,7 @@
 import org.springframework.context.annotation.ScopedProxyMode;
 
 @SpringBootApplication
-@EnableConfigurationProperties(Vaultpassword.class)
+@EnableConfigurationProperties({Vaultpassword.class, Vaultinjected.class})
 public class WrongSecretsApplication {
 
   public static void main(String[] args) {

src/main/java/org/owasp/wrongsecrets/challenges/kubernetes/Challenge46.java

@@ -0,0 +1,26 @@
+package org.owasp.wrongsecrets.challenges.kubernetes;
+
+import com.google.common.base.Strings;
+import org.owasp.wrongsecrets.challenges.FixedAnswerChallenge;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.stereotype.Component;
+
+/** This challenge is about having a secrets injected via Vault template. */
+@Component
+public class Challenge46 extends FixedAnswerChallenge {
+
+  private final Vaultinjected vaultinjected;
+  private final String mockedAnswer;
+
+  public Challenge46(Vaultinjected vaultinjected, @Value("${vaultinjected}") String mockedAnswer) {
+    this.vaultinjected = vaultinjected;
+    this.mockedAnswer = mockedAnswer;
+  }
+
+  @Override
+  public String getAnswer() {
+    return vaultinjected != null && !Strings.isNullOrEmpty(vaultinjected.getValue())
+        ? vaultinjected.getValue()
+        : mockedAnswer;
+  }
+}

src/main/java/org/owasp/wrongsecrets/challenges/kubernetes/Vaultinjected.java

@@ -0,0 +1,18 @@
+package org.owasp.wrongsecrets.challenges.kubernetes;
+
+import org.springframework.boot.context.properties.ConfigurationProperties;
+
+/** Class used to get value from vault using the springboot cloud integration with vault. */
+@ConfigurationProperties("vaultinjected")
+public class Vaultinjected {
+
+  private String value;
+
+  public void setValue(String value) {
+    this.value = value;
+  }
+
+  public String getValue() {
+    return value;
+  }
+}

src/main/resources/application.properties

@@ -12,6 +12,7 @@ CHALLENGE33=if_you_see_this_please_use_k8s
 ARG_BASED_PASSWORD=if_you_see_this_please_use_docker_instead
 DOCKER_ENV_PASSWORD=if_you_see_this_please_use_docker_instead
 vaultpassword=if_you_see_this_please_use_K8S_and_Vault
+vaultinjected=if_you_see_this_please_use_K8S_and_Vault
 spring.cloud.vault.uri=https://tobediefined.org
 spring.cloud.vault.authentication=NONE
 spring.cloud.vault.role=none
@@ -75,7 +76,7 @@ management.endpoints.web.exposure.include=auditevents,info,health
 #---
 spring.config.activate.on-profile=kubernetes-vault
 wrongsecretvalue=wrongsecret
-spring.config.import=vault://secret/secret-challenge
+spring.config.import=vault://secret/secret-challenge,vault://secret/injected
 spring.application.name=secret-challenge
 spring.cloud.vault.scheme=https://tobediefined.org
 spring.cloud.vault.enabled=true
@@ -92,7 +93,7 @@ asciidoctor.enabled=true
 #---
 spring.config.activate.on-profile=local-vault
 wrongsecretvalue=wrongsecret
-spring.config.import=vault://secret/secret-challenge
+spring.config.import=vault://secret/secret-challenge,vault://secret/injected
 spring.application.name=secret-challenge
 spring.cloud.vault.scheme=http
 spring.cloud.vault.enabled=true

src/main/resources/explanations/challenge46.adoc

@@ -0,0 +1,7 @@
+=== HashiCorp Vault Template Injection
+
+Vault template injection via agent injection typically involves injecting a sidecar container,
+known as the Vault Agent, alongside your main application container.
+The Vault Agent is responsible for interacting with HashiCorp Vault to retrieve secrets and inject them into the application's runtime environment.
+
+Can you find secret injected into application environment?

src/main/resources/explanations/challenge46_hint.adoc

@@ -0,0 +1,8 @@
+This challenge can be solved using the following steps:
+
+1. Run `kubectl get pods -A` and find secret-challenge-xxx pod name
+
+2. Run `kubectl exec secret-challenge-xxx -c secret-challenge -n default -- cat vault/secrets/challenge46` where `xxx` is the rest of the randomly generated pod name.
+to print injected secrets from vault.
+
+Note: if you are running this on a hosted environment, where you do not have access to the Kubernetes cluster, ask the organizer of the hosted solution to execute the commands for you and return the results.

src/main/resources/explanations/challenge46_reason.adoc

@@ -0,0 +1,16 @@
+*Why Vault Template Injection is not always a good idea?*
+
+While Vault agent injection via templates can be a convenient way to manage secrets in certain scenarios,
+there are situations where it might not be the best approach.
+
+Templates might accidentally expose sensitive information in logs or temporary files.
+If not properly configured, secrets could end up in places where they are accessible by unauthorized users or processes.
+
+Let's consider an example involving a template injection attack in a scripted language like PHP:
+
+. Imagine a scenario where PHP application uses a template with sensitive information
+* where template can look like this: $password = "'; system('rm -rf /'); //"
+. When the template is processed it can become:
+* $connection = "password='; system('rm -rf /'); //"
+
+To prevent such issues its crucial to ensure that the values retrieved from Vault are properly validated.

src/main/resources/wrong-secrets-configuration.yaml

@@ -738,3 +738,17 @@ configurations:
       ctf:
         enabled: true
       missing_environment: "explanations/missing_vault.adoc"
+
+    - name: Challenge 46
+      short-name: "challenge-46"
+      sources:
+        - class-name: "org.owasp.wrongsecrets.challenges.kubernetes.Challenge46"
+          explanation: "explanations/challenge46.adoc"
+          hint: "explanations/challenge46_hint.adoc"
+          reason: "explanations/challenge46_reason.adoc"
+          environments: [ *k8s_vault ]
+      difficulty: *expert
+      category: *vault
+      ctf:
+        enabled: true
+      missing_environment: "explanations/missing_vault.adoc"

src/test/java/org/owasp/wrongsecrets/challenges/cloud/ChallengesControllerWithPresetCloudValuesTest.java

@@ -21,6 +21,7 @@
       "SPECIAL_K8S_SECRET=test5",
       "SPECIAL_SPECIAL_K8S_SECRET=test6",
       "vaultpassword=test7",
+      "vaultinjected=test46",
       "secretmountpath=nothere",
       "default_aws_value_challenge_9=ACTUAL_ANSWER_CHALLENGE9",
       "default_aws_value_challenge_10=ACTUAL_ANSWER_CHALLENGE10",
@@ -52,6 +53,10 @@ void shouldSpoilExercises() throws Exception {
   @Test
   void shouldNotShowDisabledChallengeAnywhere() throws Exception {
     for (var challenge : challenges.getChallengeDefinitions()) {
+      var shortname = challenge.name().shortName();
+      if (shortname.contains("46")) {
+        continue;
+      }
       mvc.perform(get("/challenge/%s".formatted(challenge.name().shortName())))
           .andExpect(status().isOk())
           .andExpect(content().string(not(containsString("This challenge has been disabled."))));

src/test/java/org/owasp/wrongsecrets/challenges/kubernetes/Challenge46Test.java

@@ -0,0 +1,34 @@
+package org.owasp.wrongsecrets.challenges.kubernetes;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.junit.jupiter.api.Test;
+
+public class Challenge46Test {
+
+  @Test
+  void spoilerShouldGiveAnswerWithVault() {
+    var vaultInjected = new Vaultinjected();
+    vaultInjected.setValue("answer");
+    var challenge = new Challenge46(vaultInjected, "");
+    assertThat(challenge.spoiler().solution()).isNotEmpty();
+    assertThat(challenge.answerCorrect(challenge.spoiler().solution())).isTrue();
+  }
+
+  @Test
+  void spoilerShouldGiveAnswer() {
+    var vaultInjected = new Vaultinjected();
+    vaultInjected.setValue("");
+    var challenge = new Challenge46(vaultInjected, "answer");
+    assertThat(challenge.spoiler().solution()).isEqualTo("answer");
+    assertThat(challenge.answerCorrect(challenge.spoiler().solution())).isTrue();
+  }
+
+  @Test
+  void incorrectAnswerShouldNotSolveChallenge() {
+    var vaultInjected = new Vaultinjected();
+    vaultInjected.setValue("answer");
+    var challenge = new Challenge46(vaultInjected, "");
+    assertThat(challenge.answerCorrect("wrong answer")).isFalse();
+  }
+}

src/test/java/org/owasp/wrongsecrets/challenges/kubernetes/ChallengesControllerWithPresetKubernetesValuesTest.java

@@ -21,6 +21,7 @@
       "SPECIAL_K8S_SECRET=test5",
       "SPECIAL_SPECIAL_K8S_SECRET=test6",
       "vaultpassword=test7",
+      "vaultinjected=test46",
       "secretmountpath=nothere"
     },
     classes = WrongSecretsApplication.class)
@@ -55,7 +56,8 @@ void shouldNotShowDisabledChallengeAnywhere() throws Exception {
           || shortname.contains("10")
           || shortname.contains("11")
           || shortname.contains("44")
-          || shortname.contains("45")) {
+          || shortname.contains("45")
+          || shortname.contains("46")) {
         continue;
       }
       mvc.perform(get("/challenge/%s".formatted(challenge.name().shortName())))
@@ -81,7 +83,8 @@ void shouldEnableK8sExercises() throws Exception {
         .andExpect(content().string(not(containsString("challenge-6_disabled-link"))))
         .andExpect(
             content().string(containsString("challenge-7_disabled-link"))) // vault is not visible
-        .andExpect(content().string(not(containsString("challenge-33_disabled-link"))));
+        .andExpect(content().string(not(containsString("challenge-33_disabled-link"))))
+        .andExpect(content().string(containsString("challenge-46_disabled-link")));
   }
 
   @Test