What is CVE-2026-86178?

CVE-2026-86178 is a medium-severity vulnerability in Pixelfed, classified under Missing Authorization. CVSS score: 5.4/10. Published 2026-09-05.

How severe is CVE-2026-86178?

Medium severity. CVSS v3 base score is 5.4 out of 10.

Auth bypass in Pixelfed

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.

Vulnerability class: Broken Access Control

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N.

Affected products

Pixelfed

Weakness classification (CWE)

CWE-862 — Missing Authorization

References

disclosure@vulncheck.com (exploit, third-party-advisory)
disclosure@vulncheck.com (product)
disclosure@vulncheck.com (technical-description)
disclosure@vulncheck.com (technical-description)
disclosure@vulncheck.com (technical-description)
disclosure@vulncheck.com (third-party-advisory)

Frequently asked questions

What is CVE-2026-86178?: CVE-2026-86178 is a medium-severity vulnerability in Pixelfed, classified under Missing Authorization. CVSS score: 5.4/10. Published 2026-09-05.
How severe is CVE-2026-86178?: Medium severity. CVSS v3 base score is 5.4 out of 10.