CVE-2025-57727: JetBrains IntelliJ IDEA Disclosure Flaw

CVE-2025-57727 Overview

CVE-2025-57727 is an information disclosure vulnerability in JetBrains IntelliJ IDEA versions prior to 2025.2. The flaw allows credentials disclosure through a remote reference, exposing sensitive authentication data over the network. The vulnerability is classified under [CWE-319] (Cleartext Transmission of Sensitive Information) and affects developer workstations that use IntelliJ IDEA for integrated source control and remote project operations. An attacker can leverage this weakness without authentication or user interaction, making it suitable for opportunistic credential harvesting in enterprise development environments.

Critical Impact

Unauthenticated remote attackers can obtain stored credentials from vulnerable IntelliJ IDEA instances, enabling subsequent access to source code repositories and connected developer services.

Affected Products

• JetBrains IntelliJ IDEA versions before 2025.2
• Installations using remote references for project or repository integration
• All editions (Community and Ultimate) within the affected version range

Discovery Timeline

• 2025-08-20 - CVE-2025-57727 published to NVD
• 2025-08-21 - Last updated in NVD database

Technical Details for CVE-2025-57727

Vulnerability Analysis

The vulnerability resides in how IntelliJ IDEA handles remote references within projects. When the IDE processes a crafted remote reference, it discloses stored credentials to the referenced endpoint. This behavior maps directly to [CWE-319], where sensitive data traverses an untrusted channel without adequate protection. The flaw is exploitable over the network with low attack complexity and requires no privileges or user interaction. According to vendor disclosure, no exploit code is publicly available, and the issue is not listed in the CISA Known Exploited Vulnerabilities catalog.

Root Cause

The root cause is improper handling of credentials when IntelliJ IDEA resolves a remote reference. The IDE attaches authentication material to outbound requests without sufficiently validating the destination, allowing credentials to leak to attacker-controlled endpoints embedded in project configuration or remote references.

Attack Vector

The attack vector is network-based. An attacker delivers or plants a project containing a malicious remote reference, or coerces the IDE into resolving an attacker-controlled URL. When IntelliJ IDEA processes the reference, it transmits stored credentials to the remote endpoint. The attacker then captures these credentials and reuses them against connected services such as version control systems or package registries.

// No public proof-of-concept code is available for CVE-2025-57727.
// Refer to the JetBrains security advisory for technical details:
// https://www.jetbrains.com/privacy-security/issues-fixed/

Detection Methods for CVE-2025-57727

Indicators of Compromise

• Outbound HTTP or HTTPS requests from idea.exe or idea64.exe to unexpected external hosts carrying authorization headers
• IntelliJ IDEA project files containing remote references pointing to untrusted or newly registered domains
• Unexpected authentication events on Git, package registry, or CI/CD services originating from developer workstations

Detection Strategies

• Inventory IntelliJ IDEA installations and flag versions below 2025.2 using endpoint software inventory tools
• Inspect project repositories for suspicious remote reference URLs introduced through pull requests or shared project templates
• Correlate developer endpoint network telemetry with credential use patterns to identify anomalous authentication flows

Monitoring Recommendations

• Monitor proxy logs for IntelliJ IDEA user-agent strings making requests to non-corporate domains
• Alert on Git, Maven, npm, or Docker registry authentications from workstations to repositories outside the approved allowlist
• Track credential rotation events and failed authentication spikes that may indicate leaked credentials being tested

How to Mitigate CVE-2025-57727

Immediate Actions Required

• Upgrade JetBrains IntelliJ IDEA to version 2025.2 or later on all developer workstations
• Rotate credentials stored within IntelliJ IDEA, including Git tokens, SSH keys, and package registry credentials
• Audit recent project imports and shared workspaces for unauthorized remote references

Patch Information

JetBrains fixed CVE-2025-57727 in IntelliJ IDEA 2025.2. Administrators should deploy the update through the JetBrains Toolbox or enterprise software distribution channels. Vendor remediation details are available in the JetBrains Security Issues Fixed advisory.

Workarounds

• Restrict outbound network access from developer workstations to an allowlist of trusted source control and package registry endpoints
• Avoid opening untrusted projects in vulnerable IntelliJ IDEA versions until the patch is applied
• Use short-lived tokens and scoped credentials for source control integrations to reduce blast radius from disclosure

# Verify installed IntelliJ IDEA version on Linux/macOS
idea --version

# Windows PowerShell: locate installed JetBrains products
Get-ChildItem "$env:LOCALAPPDATA\JetBrains\Toolbox\apps" -Recurse -Filter "build.txt" |
  ForEach-Object { "$($_.FullName): $(Get-Content $_.FullName)" }