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CVE Record

CVE-2026-9501: GNU LibreDWG Dwgread Utility decode.c decompress_R2004_section assertion

A vulnerability was determined in GNU LibreDWG up to 0.14. The impacted element is the function decompress_R2004_section of the file src/decode.c of the component Dwgread Utility. Executing a manipulation can lead to reachable assertion. The attack is restricted to local execution. The exploit has been publicly disclosed and may be utilized. This patch is called e501cb9926c1e9a07a0d1cc997f3e69e9be801c9. A patch should be applied to remediate this issue.

MediumCVSS 4.8Not KEV-listed Updated
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Glexia's Take moderate

Analyst readout for executives and security teams

Plain-English summary

CVE-2026-9501 is a crash-type flaw in GNU LibreDWG's dwgread utility. A crafted or malformed DWG file can trigger an assertion in LibreDWG 0.14 and earlier when processed locally. The documented impact is availability loss for the utility, not data theft or remote compromise.

Executive priority

Prioritize remediation for engineering, CAD, conversion, or file-ingestion systems that handle outside DWG files. This is a moderate availability issue, not a confirmed remote compromise path, but public disclosure increases operational urgency.

Technical view

The issue is CWE-617 reachable assertion in src/decode.c, function decompress_R2004_section, affecting GNU LibreDWG versions 0.1 through 0.14. The CVSS v4.0 vector is local, low complexity, low privileges, no user interaction, with low availability impact. A patch is identified as commit e501cb9926c1e9a07a0d1cc997f3e69e9be801c9.

Likely exposure

Exposure is most likely where LibreDWG dwgread or dependent local workflows process DWG files, especially files received from outside trusted channels. The source bundle does not identify network services, cloud defaults, or downstream packaged products as affected.

Exploitation context

The bundle states public exploit material has been disclosed and may be used, but KEV is false and no cited source confirms active exploitation. Attack requirements are local execution with low privileges. Treat untrusted DWG processing as the main risk scenario.

Researcher notes

Key evidence points to a reachable assertion in decompress_R2004_section and a patch commit. The provided materials do not establish active exploitation, broader product inheritance, or confidentiality and integrity impact. Further analysis should stay focused on local DWG parsing exposure and fixed-code verification.

Mitigation direction

  • Apply the LibreDWG patch identified as commit e501cb9926c1e9a07a0d1cc997f3e69e9be801c9.
  • Upgrade affected LibreDWG versions 0.14 and earlier when vendor packages include the fix.
  • Avoid processing untrusted DWG files with vulnerable dwgread builds.
  • Run DWG conversion or inspection workflows in isolated, least-privilege environments.
  • Check GNU LibreDWG and distribution vendor guidance for packaged remediation details.

Validation and detection

  • Inventory systems and pipelines using GNU LibreDWG or dwgread.
  • Confirm installed versions are newer than 0.14 or include the patch commit.
  • Review local workflows that accept externally supplied DWG files.
  • Check logs for dwgread crashes or assertion failures during DWG parsing.
  • Verify regression tests pass after applying the vendor fix.
Prepared
Confidence
high
Sources
8

Public sources used

Based on public source material and reviewed before publication.

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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cwe · low confidence lookup

CWE-617: Exact CWE lookup

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cve · low confidence lookup

CVE-2026-9501 mapping review

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Vulnerability profile CVE Program record
Severity
Medium
CVSS
4.8 (4.0)
Known Exploited
No
Published

Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P

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.

4 CVSS vectors
6 Timeline events
1 ADP providers
8 Source links

SSVC decision data

CISA-ADP CISA Coordinator
Timestamp
Version
2.0.3
Exploitation: noneAutomatable: noTechnical Impact: partial

CVSS vector scores

4 official scores

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.

Score Version Severity Vector Exploit Impact Source
4.8 CVSS 4.0 Medium CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P — — VulDB
3.3 CVSS 3.1 Low CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C 1.8 1.4 VulDB
3.3 CVSS 3.0 Low CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C 1.8 1.4 VulDB
1.7 CVSS 2.0 Low AV:L/AC:L/Au:S/C:N/I:N/A:P/E:POC/RL:OF/RC:C 3.1 2.9 VulDB

Vulnerability scoring details

Base CVSS 4.0 score

4.8 Medium
CVSS 4.0 vector shape for CVE-2026-9501 Attack VectorAttack ComplexityAttack RequirementsPrivileges RequiredUser InteractionVS ConfidentialityVS IntegrityVS AvailabilitySS ConfidentialitySS IntegritySS Availability

Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Attack Requirements
NonePresent
Privileges Required
NoneLowHigh
User Interaction
NonePassiveActive
VS Confidentiality
HighLowNone
VS Integrity
HighLowNone
VS Availability
HighLowNone
SS Confidentiality
HighLowNone
SS Integrity
HighLowNone
SS Availability
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. Source timeline VulDB

    Advisory disclosed

  2. Source timeline VulDB

    VulDB entry created

  3. CVE reserved CVE Program

    The CVE ID was reserved by the assigning CNA.

  4. Source timeline VulDB

    VulDB entry last update

  5. CVE published CVE Program

    The CVE record was published.

  6. CVE updated CVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CISA-ADP CISA ADP Vulnrichment
other:ssvc

Source materials

Affected products

Products and packages named in the record

Vendor Product Version / package Status
GNU LibreDWG 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 0.10, 0.11, 0.12, 0.13, 0.14 Listed
Weakness

CWE details

CWE-617

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

CWE-617 · source CWE mapping

CWE mapping pending import

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