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CVE Record

CVE-2021-39137: Consensus flaw during block processing in go-ethereum

go-ethereum is the official Go implementation of the Ethereum protocol. In affected versions a consensus-vulnerability in go-ethereum (Geth) could cause a chain split, where vulnerable versions refuse to accept the canonical chain. Further details about the vulnerability will be disclosed at a later date. A patch is included in the upcoming `v1.10.8` release. No workaround are available.

MediumCVSS 6.5Not KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

CVE-2021-39137 affects go-ethereum, also known as Geth. Vulnerable nodes could reject the canonical Ethereum chain during block processing, creating chain-split risk for affected operators. This is primarily an availability and operational integrity concern, not a data-theft issue in the provided sources.

Executive priority

Treat this as a prompt infrastructure maintenance item for any Ethereum operations. The business risk is service disruption, incorrect chain view, and operational inconsistency, not confirmed data compromise. Patch affected Geth nodes without waiting for exploit details.

Technical view

Affected go-ethereum versions are >=1.10.0 and <1.10.8. The vulnerability is described as a consensus flaw during block processing that could make vulnerable clients refuse the canonical chain. CVSS 3.1 is 6.5 with network attack vector, low complexity, required privileges, and high availability impact.

Likely exposure

Exposure is limited to Ethereum nodes running go-ethereum/Geth versions >=1.10.0 and <1.10.8. Organizations operating Geth-backed Ethereum infrastructure should verify versions. The source bundle names only go-ethereum as affected.

Exploitation context

The sources do not report active exploitation, KEV listing, public exploit details, or weaponized activity. Further vulnerability details were withheld in the advisory, so exploitation mechanics cannot be assessed from the provided evidence.

Researcher notes

The advisory intentionally withholds technical details and states no workaround is available. Analysis should focus on version exposure, consensus-client role, and post-upgrade chain health. Do not infer additional affected clients or exploitability beyond the supplied go-ethereum evidence.

Mitigation direction

  • Upgrade affected go-ethereum/Geth nodes to v1.10.8 or later.
  • Prioritize internet-connected or production Ethereum nodes first.
  • Do not rely on a workaround; the advisory states none are available.
  • Review official go-ethereum guidance for any later operational notes.

Validation and detection

  • Inventory all go-ethereum/Geth nodes and record their versions.
  • Confirm no production node runs >=1.10.0 and <1.10.8.
  • Check node health for sync or canonical-chain acceptance issues.
  • Verify the upgraded binary or package corresponds to v1.10.8 or later.
Prepared
Confidence
high
Sources
4

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

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cwe · low confidence lookup

CWE-436: Exact CWE lookup

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cve · low confidence lookup

CVE-2021-39137 mapping review

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Vulnerability profileCVE Program record
Severity
Medium
CVSS
6.5 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

1CVSS vectors
0Timeline events
0ADP providers
3Source links

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
6.5CVSS 3.1MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H2.83.6Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

6.5Medium
CVSS 3.1 vector shape for CVE-2021-39137Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
ethereumgo-ethereum>= 1.10.0, < 1.10.8Listed
Weakness

CWE details

CWE-436

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.