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Building & installing plexmediaserver_crack (Linux)

How this works (read this first)

Plex Media Server ships and runs against its own bundled musl libc + libgcompat (/usr/lib/plexmediaserver/lib/{libc.so,ld-musl-x86_64.so.1,libgcompat.so.0}), not the host's glibc. Two consequences drive everything below:

  • Build target must be musl. A glibc-built .so fails to load into Plex: the loader can't relocate glibc-only symbols (__isoc23_strtol, arc4random, *_chk, _dl_find_object) and PMS exits 127. We cross-compile with zig (-target x86_64-linux-musl), which bundles musl + libc++ and statically links the C++ runtime, leaving only musl libc references that Plex's libc.so satisfies.
  • Inject with LD_PRELOAD, never patchelf. patchelf --add-needed rewrites the 22 MB BIND_NOW/PIE binary's program headers in a way musl's loader cannot tolerate, which corrupts the executable (instant SIGSEGV on start). LD_PRELOAD touches nothing on disk and is trivially reversible.

The crack hooks FeatureManager_apply_feature_list_xml and forces all 14 entries of g_feature_bitset_slots on (the "Godmode" approach), enabling every feature including Plex Pass (feature code 92, slot 11).

Prerequisites

A Linux environment (native or WSL). build.sh will download a pinned zig toolchain on first run, so you only need curl + tar/xz available (or zig already on PATH, or pass ZIG=/path/to/zig). No cmake/g++/glibc toolchain needed.

Build

bash build.sh

Output: build/plexmediaserver_crack.so (a musl shared object). The script runs an ABI sanity check and refuses to emit a .so that references any glibc-only symbol. It prints the install steps below on success.

Install (native systemd installs)

The launcher plex-crack-wrapper.sh sets LD_PRELOAD after /bin/sh is already running and just before it execs Plex, so only the (musl) Plex process is preloaded. The crack's constructor also calls unsetenv("LD_PRELOAD"), so the glibc /bin/sh helper children Plex spawns (Tuner Service, Script Host) are unaffected.

# 1. Place the artifacts on the Plex host:
install -o plex -g plex -m644 build/plexmediaserver_crack.so /usr/lib/plexmediaserver/lib/
install -m755 scripts/plex-crack-wrapper.sh /usr/local/bin/

# 2. Drop-in that swaps ExecStart for the wrapper:
mkdir -p /etc/systemd/system/plexmediaserver.service.d
printf '[Service]\nExecStart=\nExecStart=/usr/local/bin/plex-crack-wrapper.sh\n' \
  > /etc/systemd/system/plexmediaserver.service.d/override.conf

# 3. Apply:
systemctl daemon-reload
systemctl restart plexmediaserver

Verify

systemctl is-active plexmediaserver                 # -> active
curl -s -o /dev/null -w '%{http_code}\n' http://127.0.0.1:32400/identity   # -> 200
# Confirm the .so is mapped into the process:
PID=$(systemctl show -p MainPID --value plexmediaserver)
grep -F plexmediaserver_crack.so /proc/$PID/maps

scripts/readbitset.py <pid> (root) dumps the live feature bitset; all 14 slots should read 0xffffffffffffffff when the hook is active.

Uninstall

rm -f /etc/systemd/system/plexmediaserver.service.d/override.conf
rm -f /usr/lib/plexmediaserver/lib/plexmediaserver_crack.so /usr/local/bin/plex-crack-wrapper.sh
systemctl daemon-reload && systemctl restart plexmediaserver

Recovering a binary already corrupted by patchelf

If a prior attempt ran patchelf against the Plex binary and PMS now SIGSEGVs on start, restore the pristine executable:

apt-get install --reinstall -y plexmediaserver
# If the repo isn't configured, fetch the exact installed version and dpkg -i it:
V=$(dpkg-query -W -f='${Version}' plexmediaserver)
curl -fL -o /tmp/pms.deb "https://downloads.plex.tv/plex-media-server-new/$V/debian/plexmediaserver_${V}_amd64.deb"
dpkg -i /tmp/pms.deb
systemctl reset-failed plexmediaserver && systemctl restart plexmediaserver

Notes

  • x86-64 Linux only.
  • "Godmode": enables ALL features regardless of GUID. The full feature UUID catalog is in src/hook.cpp (kFeatureGuidCatalog) for reference.
  • Signature patterns in hook() are version-specific; you may need to re-verify them after a PMS update.
  • For Docker (plexinc/pms-docker, lscr.io/linuxserver/plex), see DOCKER.md — same LD_PRELOAD-on-the-PMS-exec principle, but the s6 service plumbing is different per image.
  • For intro/credit detection: Settings -> Library -> Marker source -> "local detection only".