How severe is CVE-2026-27153?

CVE-2026-27153 has a CVSS 3.x base score of 2.7, rated low severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2026-27153 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (5th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-27153?

CVE-2026-27153 primarily affects Discourse. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-27153?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-27153 have an EU (EUVD) identifier?

Yes. CVE-2026-27153 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-8894.

When was CVE-2026-27153 published?

CVE-2026-27153 was published on 2026-02-26 and last updated on 2026-06-17.

CVE-2026-27153

CVE-2026-27153 is a low-severity vulnerability in Discourse with a CVSS 3.x base score of 2.7. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-863.

Key facts

Severity: Low (CVSS 3.x base score 2.7)
CVSS v4: 1.3
EPSS exploit prediction: 0% (5th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-8894
Weakness: CWE-863
Affected product: Discourse
Published: 2026-02-26
Last modified: 2026-06-17

Description

Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, moderators could export user Chat DMs via the CSV export endpoint by exploiting an overly permissive allowlist in `can_export_entity?`. The method allowed moderators to export any entity not explicitly blocked instead of restricting to an explicit allowlist. Versions 2025.12.2, 2026.1.1, and 2026.2.0 patch the issue. No known workarounds are available.

Frequently asked questions

What is CVE-2026-27153?: Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, moderators could export user Chat DMs via the CSV export endpoint by exploiting an overly permissive allowlist in `can_export_entity?`. The method allowed moderators to export any entity not explicitly blocked instead of restricting to an explicit allowlist. Versions 2025.12.2, 2026.1.1, and 2026.2.0 patch the issue. No known workarounds are available.
How severe is CVE-2026-27153?: CVE-2026-27153 has a CVSS 3.x base score of 2.7, rated low severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2026-27153 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (5th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-27153?: CVE-2026-27153 primarily affects Discourse. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-27153?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-27153 have an EU (EUVD) identifier?: Yes. CVE-2026-27153 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-8894.
When was CVE-2026-27153 published?: CVE-2026-27153 was published on 2026-02-26 and last updated on 2026-06-17.

References

https://github.com/discourse/discourse/security/advisories/GHSA-5cp2-jq8m-33mf

Affected products (2)

cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*
cpe:2.3:a:discourse:discourse:2026.2.0:*:*:*:latest:*:*:*

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