CVE-2021-31907Network attack vector

Unauthenticated plugin changes via improper permission checks

Published May 11, 2021 · Updated Aug 3, 2024

Improper access control in JetBrains TeamCity before 2020.2.2 allows remote attackers to change TeamCity plugins without authorization. JetBrains identifies the affected locus only as the permission checks for changing TeamCity plugins and has not published the faulty operation or endpoint. Network access without authentication is sufficient according to NVD's assessment, and the documented consequence is limited to unauthorized plugin changes.

CVSS severity5.3
Medium
EPSS probability0.88%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper access control in JetBrains TeamCity before 2020.2.2 allows remote attackers to change TeamCity plugins without authorization. JetBrains identifies the affected locus only as the permission checks for changing TeamCity plugins and has not published the faulty operation or endpoint. Network access without authentication is sufficient according to NVD's assessment, and the documented consequence is limited to unauthorized plugin changes.

The record

CVE
CVE-2021-31907
Published
May 11, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-732
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

5.0NIST National Vulnerability DatabaseAV:N/AC:L/Au:N/C:N/I:P/A:N
5.3NIST National Vulnerability DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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

CWE-732Incorrect Permission Assignment for Critical Resource

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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