Security readout for executives and security teams
Plain-English summary
This issue affects JetBrains TeamCity versions before 2020.2.2. The public description says permission checks for changing TeamCity plugins were implemented improperly. That matters because plugins can affect how a build server behaves, but the provided sources do not include severity, CVSS, exploitation details, or impact specifics.
Executive priority
Prioritize if TeamCity is used for production software delivery, especially on versions before 2020.2.2. Build-system compromise can create downstream business risk, but the public record here lacks severity and exploitation evidence.
Technical view
CVE-2021-31907 is an improper permission-check issue in JetBrains TeamCity plugin-change functionality before version 2020.2.2. The source bundle does not identify a CWE, CVSS vector, required privileges, attack path, or post-change impact. Analysis should therefore focus on version exposure and plugin-change governance rather than assumed exploit mechanics.
Likely exposure
Organizations running JetBrains TeamCity before 2020.2.2 are the only clearly supported exposure group from the provided sources. Internet exposure, authentication requirements, and affected configurations are not specified.
Exploitation context
The source bundle does not state active exploitation, public exploit availability, or CISA KEV listing. Treat exploitation status as unconfirmed rather than absent.
Researcher notes
The key evidence is narrow: TeamCity before 2020.2.2 had improper permission checks for changing plugins. Do not infer unauthenticated access, remote code execution, or exploit maturity from the provided sources alone.
Mitigation direction
- Upgrade TeamCity to 2020.2.2 or later where applicable.
- Review JetBrains security bulletin guidance for this CVE.
- Restrict TeamCity plugin management to trusted administrators.
- Review plugin-change audit history for unexpected modifications.
- Monitor JetBrains advisories for additional remediation details.
Validation and detection
- Inventory all TeamCity instances and record exact versions.
- Flag any TeamCity instance running before 2020.2.2.
- Confirm who can change TeamCity plugins.
- Review logs for unexpected plugin additions, updates, or removals.
- Verify remediation against the JetBrains security bulletin.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CVE-2021-31907 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://blog.jetbrains.com/CVE reference · x_refsource_MISC
- https://blog.jetbrains.com/blog/2021/05/07/jetbrains-security-bulletin-q1-2021/CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.