How serious is CVE-2026-26207?

This vulnerability has a CVSS score of 5.4 out of 10, classified as MEDIUM severity. Proof-of-concept exploit code is publicly available, making this an active threat.

Is there exploit code available for CVE-2026-26207?

Yes, proof-of-concept exploit code for CVE-2026-26207 is publicly available on GitHub and security research platforms. This increases the risk of active exploitation.

Which products are affected by CVE-2026-26207?

CVE-2026-26207 affects discourse discourse. Check the full CVE details for specific version information.

How do I fix CVE-2026-26207?

To remediate CVE-2026-26207, check for security patches from discourse. Apply all available updates and security patches. If no patch is available, implement recommended workarounds or security controls to mitigate the risk.

CVE-2026-26207

Medium

|5.4

Exploit Available

Plain English Summary

AI-powered analysis for quick understanding

This vulnerability allows any authenticated user to manipulate policies on posts they shouldn't be able to access, including private posts, and to discover which posts have policies based on error messages. It affects users of the discourse platform who have the `discourse-policy` plugin enabled and can be fixed by upgrading to the latest versions or disabling the plugin altogether.

Technical Description

Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, `discourse-policy` plugin allows any authenticated user to interact with policies on posts they do not have permission to view. The `PolicyController` loads posts by ID without verifying the current user's access, enabling policy group members to accept/unaccept policies on posts in private categories or PMs they cannot see and any authenticated user to enumerate which post IDs have policies attached via differentiated error responses (information disclosure). The issue is patched in versions 2025.12.2, 2026.1.1, and 2026.2.0 by adding a `guardian.can_see?(@post)` check in the `set_post` before_action, ensuring post visibility is verified before any policy action is processed. As a workaround, disabling the discourse-policy plugin (`policy_enabled = false`) eliminates the vulnerability. There is no other workaround without upgrading.

CVSS Vector Analysis

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredLow

User InteractionNone

Confidentiality ImpactLow

Integrity ImpactLow

Availability ImpactNone

ScopeUnchanged

Vector String

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

Exploit Resources

Search for proof-of-concept code and exploit modules

GitHub Search Exploit-DB Nuclei Templates Metasploit Vulners

Official References

NIST NVD

Est. Bounty

$741($500-$1K)

Vendor Response

Grade APatched in 4 days

Quick Information

Published

Feb 26, 2026

about 1 month ago

Last Modified

Mar 2, 2026

about 1 month ago

Vendor

discourse

Product

discourse

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