LiveActive security incident?Get immediate response
CVE Record

CVE-2021-38443: Eclipse CycloneDDS Improper Handling of Syntactically Invalid Structure

Eclipse CycloneDDS versions prior to 0.8.0 improperly handle invalid structures, which may allow an attacker to write arbitrary values in the XML parser.

MediumCVSS 6.6Not KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

CVE-2021-38443 affects Eclipse CycloneDDS before 0.8.0. A local, low-privileged attacker could trigger improper XML parsing of invalid structures, potentially causing major availability impact and limited confidentiality or integrity impact. This is not listed in CISA KEV in the provided bundle.

Executive priority

Treat as a moderate-priority remediation item. It is not KEV-listed in the supplied data, but systems with shared local access or operational dependency on CycloneDDS should be upgraded promptly.

Technical view

CycloneDDS versions before 0.8.0 mishandle syntactically invalid structures in the XML parser, which may allow arbitrary value writes. CVSS 3.1 is 6.6 with local access, low complexity, low privileges, no user interaction, and high availability impact.

Likely exposure

Exposure is likely limited to systems that include Eclipse CycloneDDS before 0.8.0 and allow local users or local processes to influence XML parser inputs or configuration handling.

Exploitation context

The provided sources indicate local access and low privileges are required. They do not show public exploitation, active exploitation, or KEV listing. Evidence is insufficient to claim remote exploitation or widespread exploitation.

Researcher notes

Focus validation on version identification and local XML parsing exposure. The source bundle does not provide exploit details or confirm active exploitation, so avoid assuming remote reachability or exploit maturity.

Mitigation direction

  • Upgrade Eclipse CycloneDDS to version 0.8.0 or later.
  • Review CISA and Eclipse guidance for vendor-specific deployment advice.
  • Restrict local write access to CycloneDDS XML configuration inputs.
  • Inventory bundled or transitive CycloneDDS copies in products and firmware.
  • Prioritize systems where local users can modify runtime configuration files.

Validation and detection

  • Check SBOMs, package manifests, and binaries for CycloneDDS versions before 0.8.0.
  • Confirm deployed products do not bundle an older CycloneDDS library.
  • Review file permissions around CycloneDDS XML configuration sources.
  • Verify remediation by recording updated CycloneDDS versions after deployment.
  • Check vulnerability scanners for CVE-2021-38443 coverage and false negatives.
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

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

cwe · low confidence lookup

CWE-228: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cve · low confidence lookup

CVE-2021-38443 mapping review

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

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
Medium
CVSS
6.6 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/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
6.6CVSS 3.1MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H1.84.7Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

6.6Medium
CVSS 3.1 vector shape for CVE-2021-38443Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

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

CWE details

CWE-228

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

CWE-228 · source CWE mapping

Improper Handling of Syntactically Invalid Structure

Improper Handling of Syntactically Invalid Structure represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs