CVE-2021-39137: Github.com/ethereum/go ethereum Ethereum Contains Consensus Flaw During Vulnerability

MODERATE
Advisory Identifier: GHSA-9856-9gg9-qcmq
CVSS 6.5
CWE-436
Published
Advisory Summary

CVE-2021-39137 is a MODERATE (CVSS 6.5) ethereum contains consensus flaw during vulnerability (CWE-436: Interpretation Conflict) affecting Github.com/ethereum/go ethereum libraries in the Go ecosystem. The issue involves ethereum contains consensus flaw during block processing. Remediation is available by upgrading affected packages to version 1.10.8.

CVE-2021-39137 at a Glance

CVE Identifier CVE-2021-39137
GHSA Identifier GHSA-9856-9gg9-qcmq
Severity MODERATE
CVSS v3.1 Base Score 6.5
CWE Classification CWE-436: Interpretation Conflict
Affected Product Github.com/ethereum/go ethereum
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 6.5

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity None (I:N)
Availability High (A:H)

How to Fix CVE-2021-39137

To remediate this vulnerability, upgrade all affected Github.com/ethereum/go ethereum dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

github.com/ethereum/go-ethereum fixed: 1.10.8
Upgrade github.com/ethereum/go-ethereum to 1.10.8
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

inspect dependencies for github.com/ethereum/go-ethereum

How to Check if You Are Affected

To determine whether your application is affected by CVE-2021-39137, inspect your project dependencies for Github.com/ethereum/go ethereum:

inspect dependencies for github.com/ethereum/go-ethereum

Analyze the terminal output to locate any version of Github.com/ethereum/go ethereum in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.10.8), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-436: Interpretation Conflict, where product a handles inputs or steps differently than product b, which causes a to perform incorrect actions based on its perception of b's state. In Github.com/ethereum/go ethereum, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Impact A vulnerability in the Geth EVM could cause a node to reject the canonical chain. ### Description A memory-corruption bug within the EVM can cause a consensus error, where vulnerable nodes obtain a different `stateRoot` when processing a maliciously crafted transaction. This, in turn, would lead to the chain being split in two forks. All Geth versions supporting the London hard fork are vulnerable (which predates London), so all users should update. This bug was exploited on Mainnet at block 13107518, leading to a minority chain split. ### Patches A patch is included in the `v1.10.8` release. The exact patch to fix the issue is contained within this [commit](https://github.com/ethereum/go-ethereum/pull/23381/commits/4d4879cafd1b3c906fc184a8c4a357137465128f) ### Workarounds No workarounds exist, save to update and/or apply the patch commit. ### References. Post-mortem [write-up](https://github.com/ethereum/go-ethereum/blob/master/docs/postmortems/2021-08-22-split-postmortem.md). ### Credits The bug was found by @guidovranken (working for [Sentnl](https://sentnl.io/) during an audit of the [Telos EVM](https://www.telos.net/evm)) and reported via bounty@ethereum.org. ### For more information If you have any questions or comments about this advisory: * Open an issue in [go-ethereum](https://github.com/ethereum/go-ethereum/) * Email us at [security@ethereum.org](mailto:security@ethereum.org)

CVE-2021-39137 Affected Github.com/ethereum/go ethereum Versions

1 component(s)
Fixed Versions:
1.10.8
Product / Package Ecosystem Affected Versions Fixed Version
github.com/ethereum/go-ethereum
Go
≥ 1.10.0
< 1.10.8
1.10.8

References

Frequently Asked Questions

What is CVE-2021-39137?
CVE-2021-39137 is a security vulnerability in Github.com/ethereum/go ethereum involving Ethereum Contains Consensus Flaw During Block Processing under CWE-436: Interpretation Conflict.
Which Github.com/ethereum/go ethereum versions are affected?
Affected versions include releases prior to 1.10.8 across affected packages: github.com/ethereum/go-ethereum.
What version fixes CVE-2021-39137?
Upgrading to 1.10.8 (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/ethereum/go-ethereum affected?
Yes, github.com/ethereum/go-ethereum is affected in releases prior to 1.10.8. Upgrade your dependency to 1.10.8 or later.
What is the CVSS score of CVE-2021-39137?
CVE-2021-39137 has a CVSS v3.1 base score of 6.5 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
What CWE is associated with CVE-2021-39137?
CVE-2021-39137 is classified under CWE-436: Interpretation Conflict (Product A handles inputs or steps differently than Product B, which causes A to perform incorrect actions based on its perception of B's state.).
How can I check Go dependencies for CVE-2021-39137?
Run the dependency tree command: 'inspect dependencies for github.com/ethereum/go-ethereum'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-9856-9gg9-qcmq",
  "modified" : "2025-01-30T14:37:30Z",
  "published" : "2021-08-30T16:15:41Z",
  "aliases" : [ "CVE-2021-39137" ],
  "summary" : "Ethereum Contains Consensus Flaw During Block Processing",
  "details" : "### Impact\n\nA vulnerability in the Geth EVM could cause a node to reject the canonical chain. \n\n### Description \n\nA memory-corruption bug within the EVM can cause a consensus error, where vulnerable nodes obtain a different `stateRoot` when processing a maliciously crafted transaction. This, in turn, would lead to the chain being split in two forks.\n\nAll Geth versions supporting the London hard fork are vulnerable (which predates London), so all users should update.\n\nThis bug was exploited on Mainnet at block 13107518, leading to a minority chain split. \n\n### Patches\n\nA patch is included in the `v1.10.8` release.\nThe exact patch to fix the issue is contained within this [commit](https://github.com/ethereum/go-ethereum/pull/23381/commits/4d4879cafd1b3c906fc184a8c4a357137465128f)\n\n### Workarounds\n\nNo workarounds exist, save to update and/or apply the patch commit. \n\n### References. \n\nPost-mortem [write-up](https://github.com/ethereum/go-ethereum/blob/master/docs/postmortems/2021-08-22-split-postmortem.md).\n\n### Credits\n\nThe bug was found by @guidovranken (working for [Sentnl](https://sentnl.io/) during an audit of the [Telos EVM](https://www.telos.net/evm)) and reported via bounty@ethereum.org.\n\n### For more information\nIf you have any questions or comments about this advisory:\n\n* Open an issue in [go-ethereum](https://github.com/ethereum/go-ethereum/)\n* Email us at [security@ethereum.org](mailto:security@ethereum.org)\n",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/ethereum/go-ethereum"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "1.10.0"
      }, {
        "fixed" : "1.10.8"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/ethereum/go-ethereum/security/advisories/GHSA-9856-9gg9-qcmq"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-39137"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/ethereum/go-ethereum/pull/23381/commits/4d4879cafd1b3c906fc184a8c4a357137465128f"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/ethereum/go-ethereum"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/ethereum/go-ethereum/releases/tag/v1.10.8"
  }, {
    "type" : "WEB",
    "url" : "https://pkg.go.dev/vuln/GO-2022-0254"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-436" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-08-26T15:08:22Z",
    "nvd_published_at" : "2021-08-24T16:15:00Z"
  }
}