CVE-2021-41163

highpriority · attend · 46EPSS 0.198 · 97 %ileEUUS

grimoire priorityP1 · Urgent

Exploitable?

—

no known exploitation

Likely / severe?

19.8% (97th) EPSS

CVSS 7.5 · high

Is it mine?

6 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · osv · nvd

EPSS · scored 2026-10-27

Discourse is an open source platform for community discussion. In affected versions maliciously crafted requests could lead to remote code execution. This resulted from a lack of validation in subscribe_url values. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. To workaround the issue without updating, requests with a path starting /webhooks/aws path could be blocked at an upstream proxy.

cvss

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

10.0

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.5–10

v2.07.5highAV:N/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 10 · impact 6.4

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

v3.110criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Hsecondary · ENISA EU

v3.110criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Hsecondary · security-advisories@github.comexploitability 3.9 · impact 6

v3.19criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-74USprimary

affected products (6)

Products and version ranges known to be affected.

discourse discoursebeta → 2.8.0.beta7enisa_euvdEU
discourse discoursestable → 2.7.9enisa_euvdEU
discourse discoursetests-passed → 2.8.0.beta7enisa_euvdEU
discourse discourse< 2.7.9nvdUScpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*
discourse discourse= 2.8.0nvdUScpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*
Bitnami discourse< 2.7.9osvUSpkg:bitnami/discourse

advisories (1)

Vendor and ecosystem advisories describing this.

BIT-discourse-2021-41163RCE via malicious SNS subscription payload2024-03-06vendor · osvUS
Discourse is an open source platform for community discussion. In affected versions maliciously crafted requests could lead to remote code execution. This resulted from a lack of validation in subscribe_url values. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. To workaround the issue without updating, requests with a path starting /webhooks/aws path could be blocked at an upstream proxy.

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 2021-10-20modified 2026-06-17

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+5979 more

references (8)

External citations — patches, advisories, analysis.

scry

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