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GHSA-f5cx-5wr3-5qrc

HIGH

Reference binding to nullptr in boosted trees

Also known asBIT-tensorflow-2021-37662CVE-2021-37662PYSEC-2021-284PYSEC-2021-575PYSEC-2021-773
Published
Aug 25, 2021
Updated
Mar 13, 2026
Affected
9 pkgs
Patched
9 / 9
Exploits
None indexed

EPSS Exploitation Probability

via FIRST.org ↗
0.2%probability of exploitation in next 30 days
Lower Risk9th percentile+0.08%
0.00%0.23%0.46%0.69%0.0%0.2%Dec 25Apr 26Jun 26

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

9 pkgs affected
🐍tensorflow🐍tensorflow🐍tensorflow🐍tensorflow-cpu🐍tensorflow-cpu🐍tensorflow-cpu🐍tensorflow-gpu🐍tensorflow-gpu+1 more

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.

Description

Impact

An attacker can generate undefined behavior via a reference binding to nullptr in BoostedTreesCalculateBestGainsPerFeature:

import tensorflow as tf

tf.raw_ops.BoostedTreesCalculateBestGainsPerFeature(
  node_id_range=[],
  stats_summary_list=[[1,2,3]],
  l1=[1.0],
  l2=[1.0],
  tree_complexity =[1.0],
  min_node_weight =[1.17],
  max_splits=5)

A similar attack can occur in BoostedTreesCalculateBestFeatureSplitV2:

import tensorflow as tf
                                                                                                                                                                                                                                                                                          
tf.raw_ops.BoostedTreesCalculateBestFeatureSplitV2(
  node_id_range=[],
  stats_summaries_list=[[1,2,3]],
  split_types=[''],
  candidate_feature_ids=[1,2,3,4],
  l1=[1],     
  l2=[1],
  tree_complexity=[1.0],
  min_node_weight=[1.17],
  logits_dimension=5)

The implementation does not validate the input values.

Patches

We have patched the issue in GitHub commit 9c87c32c710d0b5b53dc6fd3bfde4046e1f7a5ad and in commit. 429f009d2b2c09028647dd4bb7b3f6f414bbaad7.

The fix will be included in TensorFlow 2.6.0. We will also cherrypick this commit on TensorFlow 2.5.1, TensorFlow 2.4.3, and TensorFlow 2.3.4, as these are also affected and still in supported range.

For more information

Please consult our security guide for more information regarding the security model and how to contact us with issues and questions.

Attribution

This vulnerability has been reported by members of the Aivul Team from Qihoo 360.

Affected Packages

9 total 9 fixed
EcosystemPackageVulnerable rangeFix
🐍PyPItensorflowall versions2.3.4
🐍PyPItensorflow2.4.0&&< 2.4.32.4.3
🐍PyPItensorflow2.5.0&&< 2.5.12.5.1
🐍PyPItensorflow-cpuall versions2.3.4
🐍PyPItensorflow-cpu2.4.0&&< 2.4.32.4.3
🐍PyPItensorflow-cpu2.5.0&&< 2.5.12.5.1

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for tensorflow. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

  2. Fix

    Update tensorflow to 2.3.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-f5cx-5wr3-5qrc is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 pinpoints whether GHSA-f5cx-5wr3-5qrc is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-f5cx-5wr3-5qrc. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Impact An attacker can generate undefined behavior via a reference binding to nullptr in `BoostedTreesCalculateBestGainsPerFeature`: ```python import tensorflow as tf tf.raw_ops.BoostedTreesCalculateBestGainsPerFeature( node_id_range=[], stats_summary_list=[[1,2,3]], l1=[1.0], l2=[1.0], tree_complexity =[1.0], min_node_weight =[1.17], max_splits=5) ``` A similar attack can occur in `BoostedTreesCalculateBestFeatureSplitV2`: ```python import tensorflow as tf
O3 Security · Impact-Aware SCA

Is GHSA-f5cx-5wr3-5qrc in your dependencies?

O3 detects GHSA-f5cx-5wr3-5qrc across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.