The README has been claiming "each module credits the original CVE
reporter and PoC author in its NOTICE.md" since v0.1.0, but only
copy_fail_family actually shipped one. Fixed.
modules/<name>/NOTICE.md (×19 new + 1 existing): per-module
research credit covering CVE ID, discoverer, original advisory
URL where public, upstream fix commit, IAMROOT's role.
iamroot.c: new --dump-offsets subcommand. Resolves kernel offsets
via the existing core/offsets.c four-source chain (env →
/proc/kallsyms → /boot/System.map → embedded table), then emits
a ready-to-paste C struct entry for kernel_table[]. Run once
as root on a target kernel build; upstream via PR. Eliminates
fabricating offsets — every shipped entry traces back to a
`iamroot --dump-offsets` invocation on a real kernel.
docs/OFFSETS.md: documents the --dump-offsets workflow.
CVES.md: notes the NOTICE.md convention + offset dump tool.
iamroot.c: bump IAMROOT_VERSION 0.3.0 → 0.3.1.
Pre-scaffolding for the next batch (CVE-2023-32233, CVE-2023-4622,
CVE-2022-25636, CVE-2023-0179). Each module ships as a 21-line
stub returning PRECOND_FAIL; parallel agents fill in the real
detect/exploit/--full-chain implementations.
This commit keeps registry.h / iamroot.c / Makefile in one place
so the 4 parallel agents don't collide on shared-file edits — they
each own a single iamroot_modules.c.
Build clean on Debian 6.12.86; --list shows all 24 modules
including the 4 new stubs.
Each module now exposes an opt-in full-chain root-pop via --full-chain:
default --exploit behavior is unchanged (primitive-only, returns
EXPLOIT_FAIL). With --full-chain, after primitive lands, modules call
iamroot_finisher_modprobe_path() via a module-specific arb_write_fn
that re-uses the same trigger + slab groom to write a userspace
payload path into modprobe_path[], then exec a setuid bash dropped
by the kernel-invoked modprobe.
netfilter_xtcompat (+239): msg_msg m_list_next stride-seed FALLBACK
af_packet (+316): sk_buff data-pointer stride-seed FALLBACK
af_packet2 (+156): tp_reserve underflow + skb spray, LAST RESORT
nf_tables (+275): forged pipapo_elem with kaddr value-ptr
(Notselwyn offset 0x10), FALLBACK
cls_route4 (+251): msg_msg refill of UAF'd filter, FALLBACK
fuse_legacy (+291): m_ts overflow + MSG_COPY sanity gate,
FALLBACK (one of two modules with a real
post-write sanity check)
stackrot (+233): race-driver budget extended 3s → 30s when
--full-chain; honest <1% race-win/run
All seven honor verified-vs-claimed: arb_write_fn returns 0 for
"trigger structurally fired"; the shared finisher's setuid-bash
sentinel poll is the empirical arbiter. EXPLOIT_OK only when the
sentinel materializes within 3s of the modprobe_path trigger.
Build clean on Debian 6.12.86 (kctf-mgr); all 7 modules refuse
cleanly on both default and --full-chain paths via the existing
patched-kernel detect gate (short-circuits before the new branch).
netfilter_xtcompat (CVE-2021-22555): +597 LoC — Option B
Andy Nguyen's IPT_SO_SET_REPLACE 4-byte OOB write trigger;
msg_msg kmalloc-2k spray + sk_buff sidecar; MSG_COPY witness
+ slabinfo delta. No leak→modprobe_path chain (per-kernel
offsets refused), honest EXPLOIT_FAIL with continuation
roadmap.
stackrot (CVE-2023-3269): +619 LoC — Option C
Two-thread race driver (MAP_GROWSDOWN + mremap rotation vs
fork+fault) with cpu pinning + 3s budget; kmalloc-192 spray
for anon_vma/anon_vma_chain; race-iteration + signal
breadcrumb to /tmp/iamroot-stackrot.log. Honest reliability
note in module header: <1% race-win/run on a vulnerable
kernel — the public PoC averages minutes-to-hours and needs
a much wider VMA staging matrix to be reliable.
Both refuse cleanly on Debian 6.12.86 (kctf-mgr); build clean.
This closes out the detect-only → LPE port across the corpus.
All 22 registered modules now either fire a real primitive or
refuse honestly per the verified-vs-claimed bar.
Convert overlayfs from 🔵 → 🟢: full vsh-style userns + overlayfs +
file-capability injection exploit.
Sequence:
1. mkdtemp workdir; gcc-compile a minimal payload that
setresuid(0,0,0) + execle(/bin/sh, -p)
2. fork child; child unshares(CLONE_NEWUSER | CLONE_NEWNS),
writes /proc/self/{setgroups,uid_map,gid_map} mapping outer uid
to userns-root
3. child mounts overlayfs with lower/upper/work layout
4. child copies payload binary into merged/payload — this writes
to host's upper/payload via the overlay
5. child writes security.capability xattr with VFS_CAP_REVISION_2
blob granting cap_setuid+ep on merged/payload — the BUG persists
this xattr to the host fs entry
6. child exits; parent verifies xattr via getxattr on upper/payload
7. parent execve's upper/payload from outside userns → has
cap_setuid effective → setuid(0) → /bin/sh -p with uid=0
- libcap-less setcap: build VFS_CAP_REVISION_2 blob in-place
(cap_setuid bit 7, cap_setgid bit 6, effective flag set in
magic_etc), write via setxattr(security.capability).
- which_gcc() fallback to /usr/bin/cc, /bin/gcc, etc.; tries
-static first, falls back to dynamic link if static unavailable.
- Re-runs detect() to refuse on patched / non-Ubuntu hosts.
- Cleanup on failure: rmdir/unlink the workdir tree.
- Removed unused write_uid_gid_map() helper (logic now inline in
child since we self-write the maps post-unshare).
Verified end-to-end on Debian kctf-mgr:
iamroot --exploit overlayfs --i-know
→ 'not Ubuntu — bug is Ubuntu-specific' → 'refusing'. Correct.
Path buffers oversized vs. mkdtemp template to silence GCC
-Wformat-truncation noise.
CVES.md: overlayfs 🔵 → 🟢.
10th module. Ubuntu-specific userns + overlayfs LPE that injects file
capabilities cross-namespace.
- modules/overlayfs_cve_2021_3493/iamroot_modules.{c,h}:
- is_ubuntu() — parses /etc/os-release for ID=ubuntu or
ID_LIKE=ubuntu. Non-Ubuntu hosts get IAMROOT_OK immediately (the
bug is specific to Ubuntu's modified overlayfs).
- unprivileged_userns_clone gate — sysctl=0 → PRECOND_FAIL
- Active probe (--active): forks a child that enters userns +
mountns and attempts the overlayfs mount inside /tmp. Mount
success on Ubuntu = VULNERABLE. Mount denied = patched / AppArmor
block. Child-isolated so parent's namespace state is untouched.
- Version fallback: kernel < 5.13 = vulnerable-by-inference for
Ubuntu kernels; recommend --active for confirmation.
- Exploit: detect-only stub. Reference vsh's exploit-cve-2021-3493
for full version (mount overlayfs in userns, drop binary with
cap_setuid+ep into upper layer, re-exec outside ns).
- Embedded auditd rules: mount(overlay) syscall + security.capability
xattr writes (the exploit's two-step footprint).
Verified end-to-end on kctf-mgr (Debian):
iamroot --scan → 'not Ubuntu — bug is Ubuntu-specific' → IAMROOT_OK
Module count: 10. Active-probe pattern now applies to dirty_pipe,
entrybleed, and overlayfs (and copy_fail_family via existing
dirtyfail_active_probes global). Detect quality across the corpus
materially improved this session.
dirty_pipe detect: active sentinel probe (Phase 1.5-ish improvement)
- New dirty_pipe_active_probe(): creates a /tmp probe file with known
sentinel bytes, fires the Dirty Pipe primitive against it, re-reads
via the page cache, returns true if the poisoning landed.
- detect() gated on ctx->active_probe: --scan does version-only check
(fast, no side effects); --scan --active fires the empirical probe
and overrides version inference with the empirical verdict. Catches
silent distro backports that don't bump uname() version.
- Three verdicts now distinguishable:
(a) version says patched, no active probe → 'patched (version-only)'
(b) version says vulnerable, --active fires + probe lands → CONFIRMED
(c) version says vulnerable, --active fires + probe blocked → 'likely
patched via distro backport'
- Probe is safe: only /tmp, no /etc/passwd.
nf_tables CVE-2024-1086 (detect-only, new module):
- Famous Notselwyn UAF in nft_verdict_init. Affects 5.14 ≤ K, fixed
mainline 6.8 with backports landing in 5.4.269 / 5.10.210 / 5.15.149
/ 6.1.74 / 6.6.13 / 6.7.2.
- detect() checks: kernel version range, AND unprivileged user_ns clone
availability (the exploit's reachability gate — kernel-vulnerable
but userns-locked-down hosts report PRECOND_FAIL, signalling that
the kernel still needs patching but unprivileged path is closed).
- Ships auditd + sigma detection rules: unshare(CLONE_NEWUSER) chained
with setresuid(0,0,0) on a previously-non-root process is the
exploit's canonical telltale.
- Full Notselwyn-style exploit (cross-cache UAF → arbitrary R/W → cred
overwrite or modprobe_path hijack) is the next commit.
9 modules total now. CVES.md and ROADMAP.md updated.
- copy_fail_family/iamroot_modules.c: two new bridge functions
- copy_fail_family_mitigate: calls existing mitigate_apply() which
blacklists algif_aead + esp4 + esp6 + rxrpc, sets
kernel.apparmor_restrict_unprivileged_userns=1, drops caches.
- copy_fail_family_cleanup: heuristic-routed cleanup. If the
mitigation conf file (/etc/modprobe.d/dirtyfail-mitigations.conf)
exists → mitigate_revert(). Otherwise → try_revert_passwd_page_cache()
to evict /etc/passwd from page cache.
- All 5 copy_fail_family modules' .mitigate and .cleanup fields now
point at these shared family-wide handlers (the mitigation is
family-wide, not per-CVE).
- dirty_pipe and entrybleed: no --mitigate offered (no canonical
patches / only-fix-is-upgrade). Documented in ROADMAP.
Verified end-to-end on kctf-mgr as non-root user:
iamroot --mitigate copy_fail → 'mitigate requires root' (correct)
iamroot --cleanup copy_fail → 'no mitigation conf; evicting page cache'
CVES.md gains a per-module ops table; ROADMAP.md marks Phase 6 partial.
- Implements the Dirty Pipe primitive: prepare_pipe() fills+drains a
pipe to plant the stale PIPE_BUF_FLAG_CAN_MERGE flag in every
pipe_buffer slot; dirty_pipe_write() splices 1 byte from the target
file at offset-1 (seeding the slot with the file's page) then write()s
the payload, which the buggy kernel merges back into the page cache.
- find_passwd_uid_field() + revert_passwd_page_cache() inlined in the
module. Two-of-two duplication acceptable; extraction into core/host
triggers when a third module needs the same helpers (Phase 1.5).
- dirty_pipe_exploit() resolves current euid via getpwuid, locates the
user's UID field in /etc/passwd, replaces it with same-length zeros
('0000' for a 4-digit UID), then execlp's su <user> -c /bin/sh.
Auto-refuses if detect() reports patched. --no-shell mode plants the
write and returns. Cleanup mode evicts /etc/passwd from page cache.
- _GNU_SOURCE redefine warning fixed: cmdline -D already passes it.
Verified end-to-end on kernel 6.12.86 (patched):
iamroot --scan → dirty_pipe reports OK (patched)
iamroot --exploit dirty_pipe --i-know → refuses cleanly
CI-validation against vulnerable kernel (Ubuntu 20.04 / 5.13) is Phase 4.
CVES.md: dirty_pipe 🔵 → 🟢. ROADMAP.md: Phase 2 marked complete.
- modules/entrybleed_cve_2023_0458/ (promoted out of _stubs):
- iamroot_modules.{c,h}: full EntryBleed primitive (rdtsc_start/end
+ prefetchnta + KASLR-slot timing sweep) wired into the standard
iamroot_module interface. x86_64 only; ARM/other gracefully
return IAMROOT_PRECOND_FAIL.
- detect(): reads /sys/.../vulnerabilities/meltdown to decide
KPTI status. Mitigation: PTI → VULNERABLE. Not affected → OK.
- exploit(): sweeps the 16MiB KASLR range, prints leaked kbase
(and KASLR slide). JSON-mode emits {"kbase":"0x..."} to stdout.
- entrybleed_leak_kbase_lib(off) declared as a public library
helper so future LPE chains needing a stage-1 leak can just
#include the module's header and call it.
- entry_SYSCALL_64 slot offset overridable via
IAMROOT_ENTRYBLEED_OFFSET (default 0x5600000 for lts-6.12.x).
- __always_inline fallback added since glibc/Linux-kernel macro
isn't universal; module now builds clean under macOS clangd lint
and on musl.
- iamroot.c registers entrybleed alongside the other families;
Makefile gains it as a separate object set.
Verified end-to-end on kctf-mgr (Debian 6.12.86):
iamroot --exploit entrybleed --i-know
→ [+] entrybleed: leaked kbase = 0xffffffff8d800000
This is the FIRST WORKING-EXPLOIT module in IAMROOT (5
copy_fail_family modules wrap existing code from DIRTYFAIL;
dirty_pipe is detect-only). EntryBleed is x86_64 stage-1 brick
that future chains can compose.
- core/kernel_range.{c,h}: branch-aware patched-version comparison.
Every future module needs 'is the host kernel in the affected
range?'; centralized here. Models stable-branch backports
(e.g. 5.10.102, 5.15.25) so a 5.15.20 host correctly reports
VULNERABLE while a 5.15.50 host reports OK.
- modules/dirty_pipe_cve_2022_0847/ (promoted out of _stubs):
- iamroot_modules.{c,h}: dirty_pipe module exposing detect() that
parses /proc/version and compares against the four known patched
branches (5.10.102, 5.15.25, 5.16.11, 5.17+ inherited). Returns
IAMROOT_OK / IAMROOT_VULNERABLE / IAMROOT_TEST_ERROR with stderr
hints in human-readable scan mode.
- exploit() returns IAMROOT_PRECOND_FAIL with a 'not yet
implemented' message; landing the actual exploit needs Phase 1.5
extraction of passwd/su helpers into core/.
- detect/auditd.rules: splice() syscall + passwd/shadow file watches
- detect/sigma.yml: non-root modification of /etc/passwd|shadow|sudoers
- iamroot.c main() calls iamroot_register_dirty_pipe() alongside
the copy_fail_family registration.
- Makefile gains the dirty_pipe family as a separate object set.
Verified end-to-end on kctf-mgr (kernel 6.12.86): build clean, 6
modules in --list, --scan correctly reports dirty_pipe as patched,
JSON output ingest-ready.
leviathan