CVE-2021-31901Network attack vector

Authentication bypass via unenforced group two-factor policy

Published May 11, 2021 · Updated Aug 3, 2024

Authentication bypass in JetBrains Hub before 2021.1.13079 allows remote attackers with valid passwords to evade required two-factor authentication. The two-factor policy assigned through the All Users group was not properly applied, so covered accounts could complete sign-in without the configured second factor. The bypass requires a valid Hub password; JetBrains has not disclosed the responsible code path or request-handling error.

CVSS severity7.5
High
EPSS probability0.86%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in JetBrains Hub before 2021.1.13079 allows remote attackers with valid passwords to evade required two-factor authentication. The two-factor policy assigned through the All Users group was not properly applied, so covered accounts could complete sign-in without the configured second factor. The bypass requires a valid Hub password; JetBrains has not disclosed the responsible code path or request-handling error.

The record

CVE
CVE-2021-31901
Published
May 11, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1078
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 11, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.0NVDAV:N/AC:L/Au:N/C:N/I:P/A:N
7.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1078Valid Accounts

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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