CVE-2026-22774
📋 TL;DR
CVE-2026-22774 is a denial-of-service vulnerability in the Svelte devalue JavaScript library where specially crafted inputs cause excessive CPU and memory consumption during parsing. This affects any application using devalue.parse on untrusted external data, potentially leading to service disruption. The vulnerability exists due to improper validation when creating typed arrays from ArrayBuffer inputs.
💻 Affected Systems
- Svelte devalue
📦 What is this software?
Devalue by Svelte
⚠️ Risk & Real-World Impact
Worst Case
Complete denial of service through resource exhaustion, causing application unavailability and potential cascading failures in dependent systems.
Likely Case
Degraded performance or temporary service disruption when malicious inputs are processed, requiring restart of affected services.
If Mitigated
Minimal impact with proper input validation and resource limits in place, potentially causing only minor performance degradation.
🎯 Exploit Status
Exploitation requires sending specially crafted input to applications using devalue.parse. No authentication required if the parsing endpoint is exposed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 5.6.2
Vendor Advisory: https://github.com/sveltejs/devalue/security/advisories/GHSA-vw5p-8cq8-m7mv
Restart Required: Yes
Instructions:
1. Update devalue dependency to version 5.6.2 or later. 2. Run 'npm update devalue' or 'yarn upgrade devalue'. 3. Restart your application services. 4. Test that serialization/deserialization functionality works correctly.
🔧 Temporary Workarounds
Input validation and sanitization
allImplement strict input validation and size limits on data passed to devalue.parse
Resource limiting
linuxConfigure process memory and CPU limits to prevent complete system exhaustion
ulimit -v 1048576
systemctl set-property your-service.service MemoryLimit=1G
🧯 If You Can't Patch
- Implement strict input validation and reject suspicious or malformed inputs before passing to devalue.parse
- Deploy rate limiting and monitoring on endpoints that accept data for parsing to detect and block attack patterns
🔍 How to Verify
Check if Vulnerable:
Check package.json or package-lock.json for devalue version between 5.3.0 and 5.6.1 inclusiveCheck Version:
npm list devalue | grep devalueVerify Fix Applied:
Verify devalue version is 5.6.2 or higher in package.json and test parsing functionality with various inputs📡 Detection & Monitoring
Log Indicators:
- Unusually high CPU or memory usage in processes using devalue
- Application crashes or restarts following data parsing operations
- Slow response times from endpoints that process serialized data
Network Indicators:
- Large or malformed payloads sent to parsing endpoints
- Repeated requests to parsing endpoints from single sources
SIEM Query:
source="application.logs" AND ("devalue" OR "parse") AND (cpu_usage>90 OR memory_usage>90)