giscus allows unauthorized discussion creation

published 2025-07-07 16 mo ago modified 2026-06-17 4 mo ago also EUVD-2025-20284

cvss: 5.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 24%
public exploits: 0; none known

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.

Patch / fix

links 2

github.com/giscus/giscus@4b9745f commit
github.com/giscus/giscus@c43af78 commit

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 16 mo ago (2025-07-07)

Exploit prediction

0.31% chance of exploitation in the next 30 days, higher than 24% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Affected products

giscus giscus

Classification

Weakness

CWE-285 Improper Authorization

References

Sources

CVE List CVE-2025-53532
NVD CVE-2025-53532

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary