New module for Qualys's 2026-05-20 disclosure: a __ptrace_may_access logic flaw leaves a process dropping privileges briefly reachable past its dumpable boundary; pidfd_getfd(2) steals root-opened fds / authenticated channels from it. Default-distro, no userns, arch-agnostic (fd-steal, no shellcode).
detect(): version-pinned, predates-gate at pidfd_getfd's 5.6 introduction; kernel_range from Debian backports (5.10.251/6.1.172/6.12.88/7.0.7), drift-check clean. exploit(): spawns a setuid victim, pidfd_open()s it, sweeps pidfd_getfd() over its fd table during the cred-drop window, reports any uid-0-owned fd captured from a non-root context. Honest EXPLOIT_FAIL without a euid-0 witness; not yet VM-verified. mitigate(): yama ptrace_scope=2; cleanup() reverts. auditd/sigma/falco rules, NOTICE.md (Qualys TRU credit) + MODULE.md, safety rank 84.
Wiring: registry, Makefile, cve_metadata (+JSON source), verify-vm/targets.yaml (ubuntu2204 + mainline 5.15.5 target, sweep pending). Docs: README + CVES.md + docs/index.html counts 39->40 modules / 34->35 CVEs; added to not-yet-verified lists + corpus pill.
- Sync docs/CVE_METADATA.json + KEV_CROSSREF.md to match the
hand-applied core/cve_metadata.c entries from v0.9.3. Nightly
drift-check (red since 2026-05-25) now passes. Pintheft's CWE
landed as CWE-787 from NVD (was NULL in the hand-applied entry).
- Fix fragnesia (CVE-2026-46300) range table. Per NVD: bug entered
at 5.11 SKBFL_SHARED_FRAG, vulnerable through 5.15.207 / 6.1.173 /
6.6.140 / 6.12.90 / 6.18.32 / 7.0.9, fixed at .208/.174/.141/
.91/.33/.10. Prior table had one entry {7,0,9} — off-by-one and
missing every other backport. Added predates-5.11 introduction gate
+ test row.
- Update tools/verify-vm/README.md to document the v0.9.x infra:
mainline kernel pinning via kernel.ubuntu.com, per-module
provisioner hooks, two-phase prep→reboot→verify with post-reboot
kernel confirmation, GRUB_DEFAULT pinning.
- Add curl fallback for NVD lookups in refresh-cve-metadata.py.
Mirrors the CISA path's existing fallback. Prevents the silent
Python urlopen hang seen during v0.9.3 prep (55-min stuck on
CLOSE_WAIT socket; 30s timeout never fired).
Adds per-CVE triage annotations that turn SKELETONKEY's JSON output
into something a SIEM/CTI/threat-intel pipeline can route on, and a
KEV badge in --list so operators see at-a-glance which modules
cover actively-exploited bugs.
New tool — tools/refresh-cve-metadata.py:
- Discovers CVEs by scanning modules/<dir>/ (no hardcoded list).
- Fetches CISA's Known Exploited Vulnerabilities catalog
(https://www.cisa.gov/.../known_exploited_vulnerabilities.csv).
- Fetches CWE classifications from NVD's CVE API 2.0
(services.nvd.nist.gov), throttled to the anonymous
5-req/30s limit (~3 minutes for 26 CVEs).
- Hand-curated ATT&CK technique mapping (T1068 default; T1611 for
container escapes, T1082 for kernel info leaks — MITRE doesn't
publish a clean CVE→technique feed).
- Generates three outputs:
docs/CVE_METADATA.json machine-readable, drift-checkable
docs/KEV_CROSSREF.md human-readable table
core/cve_metadata.c auto-generated lookup table
- --check mode diffs the committed JSON against a fresh fetch for
CI drift detection.
New core API — core/cve_metadata.{h,c}:
struct cve_metadata { cve, cwe, attack_technique, attack_subtechnique,
in_kev, kev_date_added };
const struct cve_metadata *cve_metadata_lookup(const char *cve);
Lookup keyed by CVE id, not module name — the metadata is properties
of the CVE (two modules covering the same bug see the same metadata).
The opsec_notes field stays on the module struct because exploit
technique varies per-module (different footprints).
Output surfacing:
- --list: new KEV column shows ★ for KEV-listed CVEs.
- --module-info (text): prints cwe / att&ck / 'in CISA KEV: YES (added
YYYY-MM-DD)' between summary and operations.
- --module-info / --scan (JSON): emits a 'triage' subobject with the
full record, plus an 'opsec_notes' field at top level when set.
Initial snapshot:
- 10 of 26 modules cover KEV-listed CVEs (dirty_cow, dirty_pipe,
pwnkit, sudo_samedit, ptrace_traceme, fuse_legacy, nf_tables,
overlayfs, overlayfs_setuid, netfilter_xtcompat).
- 24 of 26 have NVD CWE mappings; 2 unmapped (NVD has no weakness
record for CVE-2019-13272 and CVE-2026-46300 yet).
- All 26 mapped to an ATT&CK technique.
Verification:
- macOS local: 33 kernel_range + clean build, --module-info shows
'in CISA KEV: YES (added 2024-05-30)' for nf_tables, --list KEV
column renders.
- Linux (docker gcc:latest): 33 + 54 = 87 passes, 0 fails.
Follow-up commits will add per-module OPSEC notes and --explain mode.
KaraZajac