PYSEC-2026-3465

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Import Source
https://github.com/pypa/advisory-database/blob/main/vulns/fiftyone/PYSEC-2026-3465.yaml
JSON Data
https://api.osv.dev/v1/vulns/PYSEC-2026-3465
Aliases
Published
2026-07-23T11:41:45Z
Modified
2026-07-23T15:00:12Z
Severity
  • 6.3 (Medium) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N CVSS Calculator
Summary
FiftyOne App server uses wildcard CORS (Access-Control-Allow-Origin: *), enabling cross-origin reads of local server data
Details

Impact

The FiftyOne App/API server (fiftyone/server/app.py) and the /media route (fiftyone/server/routes/media.py) unconditionally set a permissive CORS header (Access-Control-Allow-Origin: *) on their responses. Because the embedded App server runs locally and is unauthenticated, this allows any website a user visits to make cross-origin requests to that user's running FiftyOne server and read the responses.

Combined with the unauthenticated /media endpoint — which serves files from the local filesystem by path — the wildcard CORS policy turns a local-only file read into a remotely exploitable, drive-by data exfiltration vulnerability. A malicious web page can silently issue requests such as http://localhost:5151/media?filepath=/etc/passwd and read arbitrary files accessible to the server process (SSH keys, cloud credentials, .env files, dataset media, etc.), then exfiltrate them to an attacker-controlled endpoint.

The victim only needs to have a FiftyOne server running locally and visit a malicious page — no clicks or other interaction are required. Browsers that have shipped Private Network Access / local-network-access protections (e.g. Chromium 142+) mitigate this for some users, but Safari and Firefox do not yet, so the attack remains viable in common configurations.

Who is impacted: any user running FiftyOne (the open-source, embedded App server) locally while also browsing the web.

Not affected: media stored in cloud buckets, which is served via signed URLs on a separate origin.

Patches

Fixed in FiftyOne 1.17.0. The hard-coded Access-Control-Allow-Origin: * has been removed and the server now responds same-origin only by default, which covers local desktop usage and the supported notebook integrations (each served through a same-origin proxy or iframe).

Cross-origin access is now opt-in via a new allowed_origins config option (environment variable FIFTYONE_ALLOWED_ORIGINS), an explicit comma-separated list of trusted origins, e.g.:

export FIFTYONE_ALLOWED_ORIGINS='https://app.example.com,http://localhost:3000'

The literal value * restores the legacy wildcard behavior for users who explicitly require it and emits a warning.

Users should upgrade to FiftyOne 1.17.0 or later.

Workarounds

In affected versions there is no configuration flag to disable the wildcard CORS header without upgrading. Until you can upgrade:

  • Do not run the FiftyOne App server while browsing untrusted websites.
  • Keep the App server bound to localhost (the default) and avoid exposing it on a network interface.
  • Use a browser that enforces Private Network Access protections.

Resources

References

Affected packages

PyPI / fiftyone

Package

Name
fiftyone
View open source insights on deps.dev
Purl
pkg:pypi/fiftyone

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
1.17.0

Affected versions

0.*
0.1.0
0.1.0.1
0.1.2
0.1.3
0.2.0rc1
0.2.0
0.2.1
0.3.0
0.4.0
0.4.1
0.5.0
0.5.1
0.5.2
0.5.2.1
0.5.3
0.5.3.1
0.5.4
0.5.5
0.5.5.1
0.5.6
0.6.0
0.6.0.1
0.6.1
0.6.1.1
0.6.2
0.6.3
0.6.4
0.6.5
0.6.5.1
0.6.5.2
0.6.6
0.7.0
0.7.0.1
0.7.1
0.7.1.1
0.7.1.2
0.7.1.3
0.7.1.4
0.7.2
0.7.3
0.7.3.1
0.7.3.2
0.7.3.3
0.7.3.4
0.7.4
0.8.0
0.8.0.1
0.9.0
0.9.1
0.9.2
0.9.3
0.9.4
0.10.0
0.11.0
0.11.1
0.11.2
0.11.2.1
0.12.0
0.13.0
0.13.1
0.13.2
0.13.3
0.14.0
0.14.1
0.14.2
0.14.3
0.14.4
0.15.0
0.15.0.1
0.15.0.2
0.15.1
0.16.0
0.16.1
0.16.2
0.16.3
0.16.4
0.16.5
0.16.6
0.17.0
0.17.1
0.17.2
0.18.0rc0
0.18.0
0.18.1rc0
0.18.1rc1
0.18.1rc2
0.18.1rc3
0.18.1rc4
0.18.1rc5
0.18.1rc6
0.18.1rc7
0.18.1rc8
0.18.1rc9
0.18.1rc10
0.18.1rc11
0.18.1rc12
0.18.1rc13
0.18.1rc14
0.18.1rc15
0.18.1rc16
0.18.1rc17
0.18.1rc18
0.18.1rc19
0.18.1rc20
0.18.1rc21
0.18.1rc22
0.18.1rc23
0.18.1rc24
0.18.1rc25
0.18.1rc26
0.19.0
0.19.1rc0
0.19.1rc1
0.19.1
0.20.0
0.20.1rc1
0.20.1rc2
0.20.1rc3
0.20.1
0.21.0
0.21.1
0.21.2
0.21.3
0.21.4
0.21.5
0.21.6
0.22.0
0.22.1
0.22.2
0.22.3
0.23.0rc1
0.23.0rc2
0.23.0
0.23.1
0.23.2
0.23.3rc1
0.23.3
0.23.4
0.23.5
0.23.6
0.23.7
0.23.8
0.24.0
0.24.1
0.25.0
0.25.1
0.25.2
1.*
1.0.0
1.0.1
1.0.2
1.1.0
1.2.0
1.3.0
1.3.1
1.3.2
1.4.0
1.4.1
1.5.0
1.5.1
1.5.2
1.6.0
1.7.0
1.7.1
1.7.2
1.8.0
1.8.1
1.9.0
1.10.0
1.11.0
1.11.1
1.12.0
1.13.0
1.13.1
1.13.2
1.13.3
1.13.4
1.13.5
1.14.0
1.14.1
1.14.2
1.15.0
1.16.0

Database specific

source 
"https://github.com/pypa/advisory-database/blob/main/vulns/fiftyone/PYSEC-2026-3465.yaml"