CVE-2026-86178

Pixelfed through 0.12.9 fails to validate follower status in StoryComposeController react and comment endpoints, allowing authenticated users to access follower-only stories. Attackers can enumerate sequential story IDs and submit reactions or comments to retrieve story media URLs and author information without following the account.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/geo-chen/oss/blob/main/Pixelfed.md
https://github.com/pixelfed/pixelfed
https://github.com/pixelfed/pixelfed/blob/v0.12.9/app/Http/Controllers/StoryComposeController.php#L487-L501
https://github.com/pixelfed/pixelfed/blob/v0.12.9/app/Http/Controllers/StoryComposeController.php#L566-L580
https://github.com/pixelfed/pixelfed/blob/v0.12.9/routes/web-api.php#L154-L155
https://www.vulncheck.com/advisories/pixelfed-through-0.12.9-unauthorized-story-access-via-api

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-05 11:16

Updated : 2026-09-08 18:21

NVD link : CVE-2026-86178

Mitre link : CVE-2026-86178

CVE.ORG link : CVE-2026-86178

JSON object : View

Products Affected

No product.

CWE

CWE-862

Missing Authorization

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