Security readout for executives and security teams
Plain-English summary
CVE-2021-31900 affects JetBrains Code With Me bundled with compatible IDE versions before 2021.1. The reported issue allowed a collaboration client to open a browser on the host machine. The public bundle does not provide CVSS, CWE, detailed impact, or exploitation evidence, so urgency depends on whether older Code With Me-enabled IDEs are still used.
Executive priority
Set priority based on developer workstation exposure. This is not confirmed actively exploited, but outdated collaborative IDE tooling can affect trusted engineering environments. Ask security and platform teams to verify legacy Code With Me usage and remediate affected systems.
Technical view
The vulnerability is described as a client-to-host action control issue in JetBrains Code With Me before IDE version 2021.1: a connected client could cause a browser to open on the host. Sources do not specify authentication conditions, browser target control, persistence, code execution, or data exposure.
Likely exposure
Exposure is likely limited to organizations running JetBrains IDEs with Code With Me versions before 2021.1 and allowing collaboration sessions with clients. The source bundle does not identify specific IDE products, operating systems, or deployment configurations beyond compatible IDE versions before 2021.1.
Exploitation context
The CVE is not listed as CISA KEV in the supplied bundle, and no cited source claims active exploitation. Public details are sparse, so treat exploitability and impact as incomplete rather than confirmed high risk.
Researcher notes
Key gaps are CVSS, CWE, affected product granularity, preconditions, and impact boundaries. The only stated behavior is that a client could open a browser on a host. Avoid assuming code execution, credential theft, or drive-by exploitation without additional vendor evidence.
Mitigation direction
- Inventory JetBrains IDE installations that include Code With Me.
- Confirm whether any Code With Me-enabled IDEs are older than 2021.1.
- Review the JetBrains Q1 2021 security bulletin for vendor guidance.
- Upgrade affected JetBrains IDEs to a non-affected supported version where applicable.
- Limit Code With Me use until affected hosts are remediated.
Validation and detection
- Check installed JetBrains IDE versions on developer workstations.
- Verify whether Code With Me is installed or enabled.
- Identify teams that used remote collaboration sessions with untrusted clients.
- Confirm remediated systems run version 2021.1 or later, if vendor guidance applies.
- Record exceptions where older versions remain in use.
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-2021-31900 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.