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CVE Record

CVE-2021-23395: Prototype Pollution

This affects all versions of package nedb. The library could be tricked into adding or modifying properties of Object.prototype using a __proto__ or constructor.prototype payload.

HighCVSS 7.3Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

CVE-2021-23395 is a prototype pollution issue in the npm package nedb. If an application lets attacker-controlled data reach vulnerable nedb handling, the attacker may be able to change shared JavaScript object behavior. That can create confidentiality, integrity, and availability impact depending on how the application uses affected objects.

Executive priority

Treat this as a high-priority dependency risk where nedb is reachable from external input. Prioritize internet-facing or unauthenticated services first, then internal services handling partner, customer, or file-derived data.

Technical view

All versions of nedb are described as affected. The issue allows modification of Object.prototype through __proto__ or constructor.prototype data. The CVSS 3.1 score is 7.3, with network attack vector, low complexity, no privileges, no user interaction, and low confidentiality, integrity, and availability impact.

Likely exposure

Exposure is most likely in Node.js applications that directly or transitively depend on nedb and process untrusted input into database records, queries, updates, or object transformation paths.

Exploitation context

The supplied sources do not show CISA KEV listing or confirmed active exploitation. Risk remains material because the CVSS vector indicates remote, unauthenticated, low-complexity exploitation when application data flow makes the vulnerable package reachable.

Researcher notes

Evidence is strongest for affected package, vulnerability class, and CVSS characteristics. The provided bundle does not identify a patch version, upstream fix, exploit campaign, or specific application-level sink. Validate reachability before assigning emergency operational impact.

Mitigation direction

  • Inventory direct and transitive use of the nedb npm package.
  • Check Snyk and upstream guidance for current remediation availability.
  • If no fixed version is available, plan replacement or compensating controls.
  • Restrict untrusted structured input before it reaches nedb-backed data paths.
  • Add monitoring for unexpected object properties or abnormal application behavior.

Validation and detection

  • Review package manifests, lockfiles, and SBOMs for nedb usage.
  • Trace whether external input reaches nedb record or update handling.
  • Run dependency scanning that includes CVE-2021-23395 or the Snyk advisory.
  • Confirm exposed routes do not pass prototype-related keys into nedb flows.
  • Verify compensating input validation covers nested object data, not only top-level fields.
Prepared
Confidence
medium
Sources
3

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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CVE-2021-23395 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
7.3 (3.1)
Known Exploited
No
Published

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

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
2Source 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
7.3CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L3.93.4Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

7.3High
CVSS 3.1 vector shape for CVE-2021-23395Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

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

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/anedb0Listed
Weakness

CWE details

No CWE listed

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