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CVE Record

CVE-2020-7729: Arbitrary Code Execution

The package grunt before 1.3.0 are vulnerable to Arbitrary Code Execution due to the default usage of the function load() instead of its secure replacement safeLoad() of the package js-yaml inside grunt.file.readYAML.

HighCVSS 7.1Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

CVE-2020-7729 affects Grunt before 1.3.0. A YAML parsing helper used an unsafe js-yaml function, creating a path to arbitrary code execution when vulnerable Grunt processes malicious YAML. This is mainly a build-tool and dependency-chain risk, not a typical internet-facing service flaw.

Executive priority

Treat this as high-priority dependency hygiene for build and CI environments. It is less likely to be a perimeter emergency, but vulnerable build tooling can affect software integrity if untrusted YAML reaches Grunt.

Technical view

grunt.file.readYAML used js-yaml load() instead of safeLoad(), allowing unsafe YAML deserialization in Grunt versions before 1.3.0. The CVSS 3.1 score is 7.1 high, with high complexity, low privileges, and required user interaction. The published fix changed the YAML loader behavior.

Likely exposure

Organizations are exposed where Grunt below 1.3.0 exists in npm, WebJars, or OS-packaged dependencies, especially in CI/build systems that parse YAML from contributors, packages, or automation inputs.

Exploitation context

The provided sources do not show active exploitation, and this CVE is not marked CISA KEV. Practical exploitation appears to require attacker influence over YAML content that vulnerable Grunt reads, plus conditions reflected by high complexity and user interaction.

Researcher notes

The key technical issue is unsafe YAML loading in grunt.file.readYAML. Source evidence names the vulnerable package and fix pattern, but not a complete exploit chain. Focus validation on Grunt version, packaging path, and whether attacker-controlled YAML can enter build workflows.

Mitigation direction

  • Upgrade Grunt to version 1.3.0 or later.
  • Apply Debian or Ubuntu security updates where Grunt is OS-packaged.
  • Update WebJars/npm-packaged Grunt dependencies if present.
  • Review vendor guidance before choosing compensating controls.
  • Limit build pipelines from processing untrusted YAML inputs.

Validation and detection

  • Inventory package manifests and lockfiles for Grunt below 1.3.0.
  • Check CI images and developer tooling for OS-packaged Grunt.
  • Look for WebJars Grunt artifacts in Java dependency trees.
  • Confirm scanners no longer report CVE-2020-7729 after updates.
  • Review build workflows that parse externally supplied YAML.
Prepared
Confidence
high
Sources
6

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

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

description · low confidence lookup

Execution behavior lookup

The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.

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cve · low confidence lookup

CVE-2020-7729 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

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Vulnerability profileCVE Program record
Severity
High
CVSS
7.1 (3.1)
Known Exploited
No
Published

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

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
7Source 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
7.1CVSS 3.1HighCVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H/RL:O1.25.9Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

7.1High
CVSS 3.1 vector shape for CVE-2020-7729Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

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

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
n/agruntunspecifiedListed
Weakness

CWE details

No CWE listed

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