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CVE Record

CVE-2021-23392: Regular Expression Denial of Service (ReDoS)

The package locutus before 2.0.15 are vulnerable to Regular Expression Denial of Service (ReDoS) via the gopher_parsedir function.

MediumCVSS 5.3Not KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

Applications using vulnerable locutus could be slowed or temporarily tied up if an attacker can feed crafted input to gopher_parsedir. The impact is availability only, not data theft or code execution. Business urgency depends on whether that function is reachable from internet-facing or unauthenticated input paths.

Executive priority

Treat as a targeted availability risk. Prioritize internet-facing services and high-traffic systems using locutus. If gopher_parsedir is not used or not exposed to untrusted input, remediation can follow normal dependency maintenance cadence.

Technical view

CVE-2021-23392 is a Regular Expression Denial of Service issue in locutus before 2.0.15, specifically via gopher_parsedir. The CVSS 3.1 score is 5.3: network-reachable, low complexity, no privileges, no user interaction, with low availability impact.

Likely exposure

Exposure is likely limited to JavaScript applications that include locutus before 2.0.15 and call gopher_parsedir on untrusted or attacker-controlled input. Dependency presence alone may not mean exploitable reachability.

Exploitation context

The source bundle does not show CISA KEV listing or evidence of active exploitation. The risk is practical denial of service where vulnerable parsing is reachable remotely, especially in unauthenticated services or shared application workers.

Researcher notes

Evidence identifies the vulnerable package, affected version boundary, and function, but does not provide CWE mapping or active exploitation. Validate reachability before escalating severity, because the CVSS score assumes network access but the vulnerable function must be in the data path.

Mitigation direction

  • Upgrade locutus to 2.0.15 or later where feasible.
  • Check Snyk and project guidance for any additional vendor recommendations.
  • Avoid passing untrusted input to gopher_parsedir until upgraded.
  • Pin and redeploy dependencies so vulnerable versions are not reintroduced.

Validation and detection

  • Inspect package manifests and lockfiles for locutus versions before 2.0.15.
  • Identify whether application code calls gopher_parsedir directly or through wrappers.
  • Confirm whether any reachable route accepts untrusted input for that parser.
  • Use dependency scanning to verify the fixed version is deployed.
Prepared
Confidence
high
Sources
5

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-2021-23392 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
Medium
CVSS
5.3 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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
4Source 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
5.3CVSS 3.1MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L3.91.4Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

5.3Medium
CVSS 3.1 vector shape for CVE-2021-23392Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

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

CWE details

No CWE listed

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