LiveActive security incident?Get immediate response
CVE Record

CVE-2021-39525: An issue was discovered in libredwg through v0.10.1.3751.

An issue was discovered in libredwg through v0.10.1.3751. bit_read_fixed() in bits.c has a heap-based buffer overflow.

UnknownCVSS not scoredNot KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysisunknown

Security readout for executives and security teams

Plain-English summary

CVE-2021-39525 is a reported heap-based buffer overflow in LibreDWG through v0.10.1.3751. Business risk depends on whether the organization uses LibreDWG to process DWG/CAD files, especially files from external parties. The public bundle does not provide CVSS, confirmed impact, exploitation, or a named fixed version.

Executive priority

Prioritize discovery first. Escalate remediation if LibreDWG processes external DWG files in production or customer-facing workflows. Without evidence of exploitation, CVSS, or a published fix in the bundle, this should not outrank actively exploited vulnerabilities.

Technical view

The CVE description identifies bit_read_fixed() in bits.c in LibreDWG through v0.10.1.3751 as containing a heap-based buffer overflow. The record does not include CWE, CVSS, exploitability details, or remediation specifics. Treat this as a file-parsing memory safety issue requiring upstream confirmation before concluding exact impact.

Likely exposure

Likely exposure is limited to systems, applications, or pipelines that embed or execute LibreDWG and parse DWG files. Internet-facing upload or conversion services handling untrusted CAD drawings would be the main concern. The CVE metadata does not enumerate downstream products.

Exploitation context

The provided sources do not show active exploitation, and the CVE is not marked KEV. The vulnerability type suggests risk may arise from malformed DWG input, but the bundle does not confirm exploitability, required interaction, privileges, or real-world attacks.

Researcher notes

The public record is sparse: affected scope is described only as LibreDWG through v0.10.1.3751, with the vulnerable function named. No CVSS, CWE, proof status, or fixed release is included in the supplied bundle. Validate against upstream before assigning precise severity.

Mitigation direction

  • Inventory direct and bundled LibreDWG usage across engineering, CAD, and file-conversion systems.
  • Check the LibreDWG issue and project guidance for fixed versions or supported mitigations.
  • Avoid processing untrusted DWG files with affected LibreDWG builds where practical.
  • Run DWG parsing workloads with least privilege and isolation.
  • Monitor vendor or distribution advisories for package updates.

Validation and detection

  • Confirm whether installed LibreDWG versions are through v0.10.1.3751.
  • Identify services that accept external DWG files and use LibreDWG for parsing.
  • Review dependency manifests, container images, and OS packages for LibreDWG references.
  • Check upstream issue status before declaring remediation complete.
  • After updating, run existing DWG parsing regression tests.
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

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

cve · low confidence lookup

CVE-2021-39525 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
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.