CVE-2021-3138

mediumpriority · track · 41EPSS 0.031 · 88 %ileexploit · PoCEUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

1 exploit · PoC

Likely / severe?

3.11% (88th) EPSS

CVSS 5 · medium

Is it mine?

4 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-27

In Discourse 2.7.0 through beta1, a rate-limit bypass leads to a bypass of the 2FA requirement for certain forms.

cvss

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

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:P/I:N/A:Nprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.17.1highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:Psecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-307USprimary

exploits (1)

Public proof-of-concept and weaponised exploit code.

Mesh3l911/CVE-2021-3138Discource POCPoC · poc_in_github

affected products (4)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
discourse discourse≤ 2.6.0nvdUScpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*
discourse discourse= 2.7.0nvdUScpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*
Bitnami discourse≤ 2.6.0osvUSpkg:bitnami/discourse

advisories (1)

Vendor and ecosystem advisories describing this.

BIT-discourse-2021-31382024-03-06vendor · osvUS
In Discourse 2.7.0 through beta1, a rate-limit bypass leads to a bypass of the 2FA requirement for certain forms.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd osv NVD CVE.org MITRE

published 2021-01-14modified 2026-06-17

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references (12)

External citations — patches, advisories, analysis.

scry

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