CVE-2021-37681
📋 TL;DR
This CVE describes a null pointer dereference vulnerability in TensorFlow's TFLite SVDF implementation. Attackers could cause denial of service or potentially execute arbitrary code by exploiting improper null pointer handling. Users running affected TensorFlow versions with TFLite models using SVDF operations are vulnerable.
💻 Affected Systems
- TensorFlow
- TensorFlow Lite
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise if combined with other vulnerabilities, or denial of service causing application crashes.
Likely Case
Application crashes or denial of service when processing malicious TFLite models containing SVDF operations with null pointer triggers.
If Mitigated
Application stability issues or crashes contained within the TensorFlow process without system-wide impact.
🎯 Exploit Status
Exploitation requires crafting malicious TFLite models that trigger the null pointer condition in SVDF operations.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: TensorFlow 2.6.0, 2.5.1, 2.4.3, and 2.3.4
Vendor Advisory: https://github.com/tensorflow/tensorflow/security/advisories/GHSA-7xwj-5r4v-429p
Restart Required: No
Instructions:
1. Update TensorFlow to patched version: pip install --upgrade tensorflow==2.6.0 (or appropriate version). 2. Rebuild any applications using TensorFlow. 3. Test TFLite models with SVDF operations.
🔧 Temporary Workarounds
Disable SVDF operations
allAvoid using SVDF operations in TFLite models until patched
Input validation
allImplement strict validation of TFLite model inputs before processing
🧯 If You Can't Patch
- Isolate TensorFlow applications in containers with limited privileges
- Implement network segmentation to restrict access to ML inference services
🔍 How to Verify
Check if Vulnerable:
Check TensorFlow version: python -c 'import tensorflow as tf; print(tf.__version__)' and compare with affected versions.Check Version:
python -c 'import tensorflow as tf; print(tf.__version__)'Verify Fix Applied:
Verify TensorFlow version is 2.6.0+, 2.5.1+, 2.4.3+, or 2.3.4+. Test SVDF operations in TFLite models.📡 Detection & Monitoring
Log Indicators:
- Segmentation faults
- Null pointer exceptions
- TensorFlow/TFLite process crashes
Network Indicators:
- Unusual TFLite model uploads to ML services
- Repeated inference failures
SIEM Query:
process_name:tensorflow AND (event_type:crash OR error_message:"null pointer" OR error_message:"segmentation fault")🔗 References
- https://github.com/tensorflow/tensorflow/commit/5b048e87e4e55990dae6b547add4dae59f4e1c76
- https://github.com/tensorflow/tensorflow/security/advisories/GHSA-7xwj-5r4v-429p
- https://github.com/tensorflow/tensorflow/commit/5b048e87e4e55990dae6b547add4dae59f4e1c76
- https://github.com/tensorflow/tensorflow/security/advisories/GHSA-7xwj-5r4v-429p
