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CVE Record

CVE-2021-40894: A Regular Expression Denial of Service (ReDOS) vulnerability was discovered in underscore-99xp v1.7.2 when...

A Regular Expression Denial of Service (ReDOS) vulnerability was discovered in underscore-99xp v1.7.2 when the deepValueSearch function is called.

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysisunknown

Security readout for executives and security teams

Plain-English summary

CVE-2021-40894 describes a denial-of-service risk in underscore-99xp v1.7.2. When the deepValueSearch function is called, a crafted input may trigger excessive regular-expression processing, tying up application resources. The public record does not provide severity scoring, known exploitation, or a named fix.

Executive priority

Treat this as a dependency exposure review, not an emergency based on current evidence. Raise priority if internet-facing services use underscore-99xp v1.7.2 with deepValueSearch on untrusted input, because availability impact could affect customer-facing operations.

Technical view

The CVE reports a Regular Expression Denial of Service issue in underscore-99xp v1.7.2, specifically when deepValueSearch is used. Available metadata does not include CVSS, CWE, package identifiers, vulnerable CPEs, exploit details, or remediation guidance. Exposure depends on whether applications call this function with untrusted input.

Likely exposure

Likely exposure is limited to applications that include underscore-99xp v1.7.2 and invoke deepValueSearch on user-controlled or externally supplied data. The source bundle does not establish broader product impact, package ecosystem prevalence, or affected versions beyond v1.7.2.

Exploitation context

The CVE is not listed as KEV, and the provided sources do not claim active exploitation. The issue class can support denial of service when vulnerable code processes hostile input, but public evidence here is too sparse to assess real-world exploitability.

Researcher notes

The public record is sparse: no CVSS, CWE, CPE, affected package coordinates, exploit status, or fix version is provided. Analysis should stay anchored to the named function and version until maintainers or additional authoritative advisories clarify scope.

Mitigation direction

  • Inventory applications and SBOMs for underscore-99xp v1.7.2.
  • Check project or vendor guidance for patched versions or replacement recommendations.
  • Avoid passing untrusted input into deepValueSearch where feasible.
  • Add request timeouts and resource controls around exposed processing paths.
  • Consider replacing the dependency if no maintained fix exists.

Validation and detection

  • Search dependency manifests, lockfiles, and bundled JavaScript for underscore-99xp.
  • Identify whether deepValueSearch is reachable from public or partner-controlled inputs.
  • Review application telemetry for abnormal latency or resource spikes in affected paths.
  • Run safe internal performance regression tests around deepValueSearch usage.
  • Document compensating controls when immediate dependency removal is not possible.
Prepared
Confidence
low
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

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CVE-2021-40894 mapping review

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Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
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.

0CVSS vectors
0Timeline events
0ADP providers
2Source links

CVSS and timeline data

No CVSS vectors or timeline events were available in the normalized CVE source material.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
n/an/an/aListed
Weakness

CWE details

No CWE listed

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