CVE-2024-27101
📋 TL;DR
An integer overflow vulnerability in SpiceDB's chunking helper causes permission-checking APIs to miss elements or panic when a resource has over 65,535 relationships of the same type. This affects CheckPermission, BulkCheckPermission, and LookupSubjects methods, potentially leading to incorrect authorization decisions. Any SpiceDB cluster with schemas containing such high-relationship resources is vulnerable.
💻 Affected Systems
- SpiceDB
📦 What is this software?
Spicedb by Authzed
⚠️ Risk & Real-World Impact
Worst Case
Authorization bypass where legitimate access is denied (panic) or unauthorized access is granted (missed elements), compromising security-critical permissions.
Likely Case
Service disruption through panics or incorrect permission evaluations in applications relying on SpiceDB for authorization.
If Mitigated
Limited impact if relationship counts stay below 65,535 threshold or if redundancy handles panics gracefully.
🎯 Exploit Status
Exploitation requires API access and specific data conditions; no known public exploits.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.29.2
Vendor Advisory: https://github.com/authzed/spicedb/security/advisories/GHSA-h3m7-rqc4-7h9p
Restart Required: Yes
Instructions:
1. Backup your SpiceDB data. 2. Update SpiceDB to version 1.29.2 using your package manager or from GitHub releases. 3. Restart the SpiceDB service.
🔧 Temporary Workarounds
Limit relationship counts
allMonitor and ensure no resource exceeds 65,535 relationships of the same type to avoid triggering the vulnerability.
🧯 If You Can't Patch
- Implement rate limiting or validation to reject API calls that could trigger the overflow condition.
- Deploy redundant SpiceDB instances to handle potential panics gracefully with failover mechanisms.
🔍 How to Verify
Check if Vulnerable:
Check if SpiceDB version is below 1.29.2 and if any resources have >65,535 relationships of same type via database queries or monitoring.Check Version:
spicedb versionVerify Fix Applied:
Confirm SpiceDB version is 1.29.2 or higher and test permission checks with high-relationship resources to ensure no panics or missed elements.📡 Detection & Monitoring
Log Indicators:
- Panic logs from SpiceDB processes
- Errors in CheckPermission/BulkCheckPermission/LookupSubjects API responses
Network Indicators:
- Increased error rates in authorization API calls
- Unusual patterns in relationship data queries
SIEM Query:
source="spicedb" AND (log_level="panic" OR message="integer overflow")🔗 References
- https://github.com/authzed/spicedb/commit/ef443c442b96909694390324a99849b0407007fe
- https://github.com/authzed/spicedb/security/advisories/GHSA-h3m7-rqc4-7h9p
- https://github.com/authzed/spicedb/commit/ef443c442b96909694390324a99849b0407007fe
- https://github.com/authzed/spicedb/security/advisories/GHSA-h3m7-rqc4-7h9p
