Discourse: Information Disclosure in Form Template API Due to Missing Authorization

published 2026-05-19 5 mo ago modified 2026-09-08 2 mo ago also BIT-discourse-2026-33514 , EUVD-2026-30821 , GHSA-w6g7-p2p9-2m5h

cvss: 4.3; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 16%
public exploits: 0; none known

Discourse is an open-source discussion platform. In versions prior to 2026.1.4, 2026.3.1, 2026.4.1 and 2026.5.0-latest.1, an authenticated user on a Discourse instance with the form templates feature enabled can read the name and structured content of form templates that are intended exclusively for categories they are not authorized to access. Impact is limited to disclosure of site configuration metadata. This issue has been fixed in versions 2026.1.4, 2026.3.1, 2026.4.1 and 2026.5.0-latest.1.

Patch / fix

fixed in 2 links 1

bitnami discourse 2026.1.4, 2026.3.1, 2026.4.1
discourse discourse 2026.1.4, 2026.3.1, 2026.4.1, 2026.5.0-latest.1

github.com/discourse/discourse@ae5c957 commit

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 5 mo ago (2026-05-19)

Exploit prediction

0.25% chance of exploitation in the next 30 days, higher than 16% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	6.0	CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
CNA	4.0	6.0	CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD	3.1	4.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Affected packages

ecosystem	package	affected	fixed in
bitnami	discourse	<2026.1.4 >=2026.3.0, <2026.3.1 >=2026.4.0, <2026.4.1	2026.1.4 2026.3.1 2026.4.1

Affected products

discourse discourse

Classification

Weakness

CWE-862 Missing Authorization

References

github.com /discourse/discourse/commit/ae5c9570fb918442c4d96abc83c1e7e169909b02
patch
github.com /discourse/discourse/security/advisories/GHSA-w6g7-p2p9-2m5h
vendor-advisory, advisory
nvd.nist.gov /vuln/detail/CVE-2026-33514
web

Sources

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.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.

Summary