CVE-2026-28282 json
Discourse vulnerable to group membership addition permission bypass via discourse-policy plugin
published 7mo ago modified last mo. also BIT-discourse-2026-28282 , EUVD-2026-13243 , GHSA-6cc8-x3rm-j5pf
- cvss
- 6.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 29%
- public exploits
- 0
- none known
Summary
Discourse is an open-source discussion platform. Versions prior to 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 have a security flaw in the discourse-policy plugin which allowed a user with policy creation permission to gain membership access to any private/restricted groups. Once membership to a private/restricted group has been obtained, the user will be able to read private topics that only the group has access to. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. As a workaround, review all policies for the use of `add-users-to-group` and temporarily remove the attribute from the policy. Alternatively, disable the discourse-policy plugin by disabling the `policy_enabled` site setting.
Patch / fix
- bitnami discourse 2026.1.2, 2026.2.1, 2026.4.0
- discourse discourse 2026.1.2, 2026.2.1
Is CVE-2026-28282 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 7mo ago
Exploit prediction
0.35% chance of exploitation in the next 30 days, higher than 29% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 2.3 | CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N |
| CNA | 4.0 | 2.3 | CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/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 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N |
| OSV | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| bitnami | discourse | >=2026.1.0, <2026.1.2 >=2026.2.0, <2026.2.1 >=2026.3.0, <2026.4.0 |
2026.1.2 2026.2.1 2026.4.0 |
Affected products
- discourse discourse
Classification
- Weakness
-
- CWE-863 Incorrect Authorization
References
-
github.com
/discourse/discourse/commit/64e2514ac17046cfaa8bc68a3c5140bc40736add
patch
-
github.com
/discourse/discourse/commit/c14b8a4cc5fc94e4839a83c5d55765897589f45b
patch
-
github.com
/discourse/discourse/commit/dcde9de530f515e88f99957056ffbcc2e1e03951
patch
-
github.com
/discourse/discourse/security/advisories/GHSA-6cc8-x3rm-j5pf
vendor-advisory, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-28282
web
Sources
- CVE List CVE-2026-28282
- NVD CVE-2026-28282
- OSV BIT-discourse-2026-28282
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