leviathan
023289a03a
Previous banner had a SKELETONKEY block-letter art that competed with the skeleton-key drawing for visual attention. Simplified: the key art is now the focal point, and SKELETONKEY is rendered as plain spaced text below the drawing. Slight refinement to the key art: bow is a bit larger (888 instead of 88) to feel more substantial. Bit/teeth pattern unchanged. Bump 0.4.2 → 0.4.3.
172 lines
6.7 KiB
Markdown
172 lines
6.7 KiB
Markdown
# SKELETONKEY
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> A curated, actively-maintained corpus of Linux kernel LPE exploits —
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> bundled with their detection signatures, patch status, and version
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> ranges. Run it on a system you own (or are authorized to test) and
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> it tells you which historical and recent CVEs that system is still
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> vulnerable to, and — with explicit confirmation — gets you root.
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```
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,d8888b,
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d88' `88b
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d88' ,db, `88b
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888 d8''8b 888===========================================,
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888 88 88 888 `=,
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888 `8bd8' 888 "Yb,
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`88b `""' d88' Yb
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`Y8, ,8P' ,d8'
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`"Y8P"' ,d8P'
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d8P"
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S K E L E T O N K E Y
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```
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> ⚠️ **Authorized testing only.** SKELETONKEY is a research and red-team
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> tool. By using it you assert you have explicit authorization to test
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> the target system. See [`docs/ETHICS.md`](docs/ETHICS.md).
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## Quickstart
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```bash
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# One-shot install (x86_64 / arm64; checksum-verified)
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curl -sSL https://github.com/KaraZajac/SKELETONKEY/releases/latest/download/install.sh | sh
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```
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**skeletonkey runs as a normal unprivileged user** — that's the whole
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point. `--scan`, `--audit`, `--exploit`, and `--detect-rules` all
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work without `sudo`. Only `--mitigate` and rule-file installation
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write to root-owned paths.
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```bash
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# What's this box vulnerable to? (no sudo)
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skeletonkey --scan
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# Broader system hygiene (setuid binaries, world-writable, capabilities, sudo)
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skeletonkey --audit
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# Deploy detection rules (needs sudo to write /etc/audit/rules.d/)
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skeletonkey --detect-rules --format=auditd | sudo tee /etc/audit/rules.d/99-skeletonkey.rules
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# Apply temporary mitigations (needs sudo for modprobe.d + sysctl)
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sudo skeletonkey --mitigate copy_fail
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# Fleet scan (any-sized host list via SSH; aggregated JSON for SIEM)
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./tools/skeletonkey-fleet-scan.sh --binary skeletonkey --ssh-key ~/.ssh/id_rsa hosts.txt
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```
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### Example: unprivileged → root
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```text
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$ id
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uid=1000(kara) gid=1000(kara) groups=1000(kara)
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$ skeletonkey --scan
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[+] dirty_pipe VULNERABLE (kernel 5.15.0-56-generic)
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[+] cgroup_release_agent VULNERABLE (kernel 5.15 < 5.17)
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[+] pwnkit VULNERABLE (polkit 0.105-31ubuntu0.1)
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[-] copy_fail not vulnerable (kernel 5.15 < introduction)
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[-] dirty_cow not vulnerable (kernel ≥ 4.9)
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$ skeletonkey --exploit dirty_pipe --i-know
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[!] dirty_pipe: kernel 5.15.0-56-generic IS vulnerable
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[+] dirty_pipe: writing UID=0 into /etc/passwd page cache...
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[+] dirty_pipe: spawning su root
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# id
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uid=0(root) gid=0(root) groups=0(root)
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```
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`skeletonkey --help` lists every command. See [`CVES.md`](CVES.md) for
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the curated CVE inventory and [`docs/DEFENDERS.md`](docs/DEFENDERS.md)
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for the blue-team deployment guide.
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## What this is
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Most Linux LPE references are dead repos, broken PoCs, or single-CVE
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deep-dives. **SKELETONKEY is a living corpus**: each CVE that lands here
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is empirically verified to work on the kernels it claims to target,
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CI-tested across a distro matrix, and ships with the detection
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signatures defenders need to spot it in their environment.
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The same binary covers offense and defense:
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- `skeletonkey --scan` — fingerprint the host, report which bundled CVEs
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apply, and which are blocked by patches/config/LSM
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- `skeletonkey --exploit <CVE>` — run the named exploit (with `--i-know`
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authorization gate)
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- `skeletonkey --detect-rules` — dump auditd / sigma / yara rules for
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every bundled CVE so blue teams can drop them into their tooling
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- `skeletonkey --mitigate` — apply temporary mitigations for CVEs the
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host is vulnerable to (sysctl knobs, module blacklists, etc.)
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## Status
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**Active — v0.3.0 cut 2026-05-16.** Corpus covers **24 modules**
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across the 2016 → 2026 LPE timeline:
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- 🟢 **13 modules land root** end-to-end on a vulnerable host
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(copy_fail family ×5, dirty_pipe, entrybleed leak, pwnkit,
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overlayfs CVE-2021-3493, dirty_cow, ptrace_traceme,
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cgroup_release_agent, overlayfs_setuid CVE-2023-0386).
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- 🟡 **11 modules fire the kernel primitive** by default and refuse
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to claim root without empirical confirmation. Pass `--full-chain`
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to engage the shared `modprobe_path` finisher and attempt root
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pop — requires kernel offsets via env vars / `/proc/kallsyms` /
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`/boot/System.map`; see [`docs/OFFSETS.md`](docs/OFFSETS.md).
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Modules: af_packet, af_packet2, af_unix_gc, cls_route4,
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fuse_legacy, nf_tables, netfilter_xtcompat, nft_fwd_dup,
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nft_payload, nft_set_uaf, stackrot.
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- Detection rules ship inline (auditd / sigma / yara / falco) and
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are exported via `skeletonkey --detect-rules --format=…`.
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See [`CVES.md`](CVES.md) for the per-CVE inventory + patch status.
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See [`ROADMAP.md`](ROADMAP.md) for the next planned modules.
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## Why this exists
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The Linux kernel privilege-escalation space is fragmented:
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- **`linux-exploit-suggester` / `linpeas`**: suggest applicable
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exploits, don't run them
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- **`auto-root-exploit` / `kernelpop`**: bundle exploits, but largely
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stale, no CI, no defensive signatures
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- **Per-CVE single-PoC repos**: usually one author, often abandoned
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within months of release, often only one distro
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SKELETONKEY's bet is that there's room for a single curated bundle that
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(1) actively maintains a small set of high-quality exploits across a
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multi-distro matrix, and (2) ships detection rules alongside each
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exploit so the same project serves both red and blue teams.
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## Architecture
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Each CVE (or tightly-related family) is a **module** under `modules/`.
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Modules export a standard interface: `detect()`, `exploit()`,
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`mitigate()`, `cleanup()`, plus metadata describing affected kernel
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ranges, distro coverage, and CI test matrix.
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Shared infrastructure (AppArmor bypass, su-exploitation primitives,
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fingerprinting, common utilities) lives in `core/`.
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See [`docs/ARCHITECTURE.md`](docs/ARCHITECTURE.md) for the
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module-loader design and how to add a new CVE.
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## Build & run
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```bash
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make # build all modules
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./skeletonkey --scan # what's this box vulnerable to? (no sudo)
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./skeletonkey --scan --json # machine-readable output for CI/SOC pipelines
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./skeletonkey --detect-rules --format=sigma > rules.yml
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./skeletonkey --exploit copy_fail --i-know # actually run an exploit (starts as $USER)
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```
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## Acknowledgments
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Each module credits the original CVE reporter and PoC author in its
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`NOTICE.md`. SKELETONKEY is the bundling and bookkeeping layer; the
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research credit belongs to the people who found the bugs.
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## License
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MIT — see [`LICENSE`](LICENSE).
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