CVE-2025-48877

criticalpriority · track · 39EPSS 0.004 · 35 %ileEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.41% (35th) EPSS

CVSS 9.8 · critical

Is it mine?

7 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · osv · nvd

EPSS · scored 2026-10-26

Discourse is an open-source discussion platform. Prior to version 3.4.4 of the `stable` branch, version 3.5.0.beta5 of the `beta` branch, and version 3.5.0.beta6-dev of the `tests-passed` branch, Codepen is present in the default `allowed_iframes` site setting, and it can potentially auto-run arbitrary JS in the iframe scope, which is unintended. This issue is patched in version 3.4.4 of the `stable` branch, version 3.5.0.beta5 of the `beta` branch, and version 3.5.0.beta6-dev of the `tests-passed` branch. As a workaround, the Codepen prefix can be removed from a site's `allowed_iframes`.

cvss

Technical severity, 0–10. One row per scoring source.

9.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 8.1–9.8

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v4.08.1highCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:Usecondary · ENISA EU

v4.08.1highCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/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:Xsecondary · security-advisories@github.com

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-1038US

affected products (7)

Products and version ranges known to be affected.

discourse discourse≤ < 3.5.0.beta5enisa_euvdEU
discourse discourse≤ < 3.5.0.beta6-devenisa_euvdEU
discourse discourse≤ < 3.4.4enisa_euvdEU
discourse discourse< 3.4.4nvdUScpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*
discourse discourse< 3.5.0nvdUScpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*
discourse discourse= 3.5.0nvdUScpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*
Bitnami discourse< 3.4.4osvUSpkg:bitnami/discourse

advisories (1)

Vendor and ecosystem advisories describing this.

BIT-discourse-2025-48877Discourse vulnerable to auto-executing of third-party code in embedded CodePen iframe2025-06-11vendor · osvUS
Discourse is an open-source discussion platform. Prior to version 3.4.4 of the `stable` branch, version 3.5.0.beta5 of the `beta` branch, and version 3.5.0.beta6-dev of the `tests-passed` branch, Codepen is present in the default `allowed_iframes` site setting, and it can potentially auto-run arbitrary JS in the iframe scope, which is unintended. This issue is patched in version 3.4.4 of the `stable` branch, version 3.5.0.beta5 of the `beta` branch, and version 3.5.0.beta6-dev of the `tests-passed` branch. As a workaround, the Codepen prefix can be removed from a site's `allowed_iframes`.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd osv nvd NVD CVE.org MITRE

published 2025-06-09modified 2026-06-17

references (5)

External citations — patches, advisories, analysis.

scry

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