CVE-2026-28282
Discourse vulnerable to group membership addition permission bypass via discourse-policy plugin
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
2.3
Discourse vulnerable to group membership addition permission bypass via discourse-policy plugin
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.
- Record
CVE-2026-28282- CVSS 4.0
- 2.3 Low
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 - Weakness
- CWE-863
- Updated
- 2026-11-02
EUVDEUVD-2026-13243
2.3
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.
- Record
EUVD-2026-13243- CVSS 4.0
- 2.3 Low
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 - Updated
- 2026-11-02
NVD
2.3
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.
- Record
CVE-2026-28282- CVSS 4.0
- 2.3 Low
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 - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-863
- Updated
- 2026-11-02
OSV
2.3
Discourse vulnerable to group membership addition permission bypass via discourse-policy plugin
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.
- Record
CVE-2026-28282- CVSS 4.0
- 2.3 Low
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 - Weakness
- CWE-863
- Updated
- 2026-11-02
OSVBIT-discourse-2026-28282 No score
Discourse vulnerable to group membership addition permission bypass via discourse-policy plugin
Discourse is an open-source discussion platform. Versions prior to 2026.3.0, 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, 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.
- Record
BIT-discourse-2026-28282- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
discourseBitnami |
2026.1.0 up to 2026.1.2, 2026.2.0 up to 2026.2.1, 2026.3.0 up to 2026.4.0 | 2026.1.22026.2.12026.4.0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-28282 is a low vulnerability (CVSS 2.3) in Discourse, published March 19, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.35%, the 29th percentile. Fixed in discourse 2026.1.2.
References
github.com/discourse/discourse/security/advisories/GHSA-6cc8-x3rm-j5pf
github.com/discourse/discourse/commit/64e2514ac17046cfaa8bc68a3c5140bc40736add
github.com/discourse/discourse/commit/c14b8a4cc5fc94e4839a83c5d55765897589f45b
github.com/discourse/discourse/commit/dcde9de530f515e88f99957056ffbcc2e1e03951
nvd.nist.gov/vuln/detail/CVE-2026-28282
github.com/CVEProject/cvelistV5/tree/main/cves/2026/28xxx/CVE-2026-28282.json