Auth bypass in Giscus

CVE-2025-53532

giscus is a commenting system powered by GitHub Discussions. A bug in giscus' discussions creation API allowed an unauthorized user to create discussions on any repository where giscus is installed. This affects the server-side part of giscus, which is provided via http://giscus.app or your own self-hosted service. This vulnerability is fixed by the c43af7806e65adfcf4d0feeebef76dc36c95cb9a and 4b9745fe1a326ce08d69f8a388331bc993d19389 commits.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (19.5th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 19th percentile — 19.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-53532: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.000

Affected products

  • Giscus — versions < c43af7806e65adfcf4d0feeebef76dc36c95cb9a

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-53532?
CVE-2025-53532 is a medium-severity vulnerability in Giscus, classified under Improper Authorization. CVSS score: 5.3/10. Published 2025-07-07.
How severe is CVE-2025-53532?
Medium severity. CVSS v3 base score is 5.3 out of 10.