PT-2026-64078 — Pypi Garmin Connect

PT-2026-64078 · Pypi · Garmin Connect

Published

2026-07-23

Updated

2026-07-23

CVSS v3.1

8.4

High

Vector

AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N

Insecure Permission Assignment for Garmin OAuth Token Store

Summary

garminconnect (≤ 0.3.4) wrote its OAuth token store to disk without restricting file-system permissions. Under the default Linux umask (022) the token file garmin tokens.json was created world-readable (0o644). The file contains the DI refresh token, so any other local user on a shared host could read it and obtain persistent, unauthorized access to the victim's Garmin Connect account.

Severity: High
Weakness: CWE-732 (Incorrect Permission Assignment for Critical Resource)
Affected versions: <= 0.3.4
Patched version: 0.3.5

Details

Client.dump() created the token directory and file with no mode argument, leaving permissions entirely to the process umask:

python

def dump(self, path: str) -> None:
  p = Path(path).expanduser()
  if p.is dir() or not p.name.endswith(".json"):
    p = p / "garmin tokens.json"
  p.parent.mkdir(parents=True, exist ok=True)  # no mode=
  p.write text(self.dumps())           # no permission restriction

The serialized payload includes di token, di refresh token, and di client id. The call is in the core library (Garmin.login(tokenstore=...) persists tokens this way), and all shipped usage examples default the token store to ~/.garminconnect.

Under umask 022 the resulting permissions were:

token directory → 0o755
garmin tokens.json → 0o644 (world-readable)

A separate, unprivileged user on the same machine could read the file with a plain open() — no elevated privileges required — and extract the refresh token.

Impact

Local credential theft / privilege escalation on multi-user Linux or macOS hosts running under a permissive umask. The stolen refresh token can be exchanged for fresh access tokens via Garmin's OAuth endpoint, granting ongoing access to the victim's account (health/fitness data, activity history, device management) until the token is revoked.

Patch

Fixed in 0.3.5 (commit 77a3837). dump() now creates the directory as 0o700 and writes the token file as 0o600 regardless of umask — using os.open(..., O CREAT|O WRONLY|O TRUNC, 0o600) with O NOFOLLOW where available, plus a defensive chmod that also tightens a pre-existing loose file:

python

p.parent.mkdir(mode=0o700, parents=True, exist ok=True)
with contextlib.suppress(OSError):
  p.parent.chmod(0o700)
flags = os.O WRONLY | os.O CREAT | os.O TRUNC
if hasattr(os, "O NOFOLLOW"):
  flags |= os.O NOFOLLOW
fd = os.open(p, flags, 0o600)
with os.fdopen(fd, "w", encoding="utf-8") as f:
  f.write(self.dumps())
with contextlib.suppress(OSError):
  p.chmod(0o600)

Verified under umask 022: directory 0o700, file 0o600, no group/other access.

Workarounds

If you cannot upgrade immediately, restrict the token store manually and keep it owner-only:

bash

chmod 700 ~/.garminconnect
chmod 600 ~/.garminconnect/garmin tokens.json

Remediation

Upgrade to garminconnect >= 0.3.5:

bash

pip install --upgrade garminconnect

Fix any token file already on disk — upgrading only tightens permissions on the next write, so an existing world-readable file stays exposed until then:

bash

chmod 600 ~/.garminconnect/garmin tokens.json
# or remove it and log in again to mint a fresh token store

If the file was exposed on a shared host, treat the refresh token as compromised. Re-authenticate (delete the token store and log in again) so a new token is issued; consider the previously stored token potentially read by others until rotated.

Credit

Reported by EQSTLab via a private security advisory. garminconnect thanks them for the detailed, responsible disclosure.

Fix

Found an issue in the description? Have something to add? Feel free to write us 👾

dbugs@ptsecurity.com

Related Identifiers

PYSEC-2026-3467

Affected Products

Garmin Connect