# CVE-2026-9504: GNU LibreDWG out-of-bounds read in Dwggrep Utility

Source: https://junglewise.ai/threats/cve-2026-9504-gnu-libredwg-out-of-bounds-read-in-dwggrep-utility  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-25. Updated: 2026-05-26  
License: CC BY 4.0 with a link back

CVE-2026-9504 · Severity: low · CVSS 3.3 · Published 2026-05-25

GNU LibreDWG is a library used for reading and writing DWG files, which are the standard format for computer-aided design (CAD) software. A vulnerability in the library's search utility could allow a local user to read sensitive information from the computer's memory by providing a specially crafted, malformed DWG file. This could lead to minor data exposure or be used as part of a more complex attack chain.

Technologies: [Gnu LibreDWG](https://junglewise.ai/threats/technologies/libredwg). Vendors: [Gnu](https://junglewise.ai/threats/vendors/gnu).

## Quick answers

**Is CVE-2026-9504 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-9504 being exploited in the wild.

**How severe is CVE-2026-9504?** Low severity, with a CVSS score of 3.3, published 25 May 2026.

**Which products and versions are affected?** Gnu LibreDWG up to 0.14.

**Is there a fix for CVE-2026-9504?** A patch was published on 2026-05-25: Patch commit be996bf2178a40e98720f18c2414815d244413db released Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-9504 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2026-9504?** Check whether you run Gnu LibreDWG at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

An out-of-bounds read vulnerability exists in GNU LibreDWG versions up to 0.14 within the Dwggrep Utility. The flaw is located in the bit_convert_TU function in programs/dwggrep.c (and src/bits.c). When processing a malformed DWG file, specifically during an LTYPE search, the application may fail to find a wide null terminator in the binary buffer. This causes the scanner to read past the allocated heap buffer. An attacker with local access can exploit this by providing a crafted DWG file to the dwggrep tool, potentially leading to information disclosure from heap memory. A patch has been released (commit be996bf) which introduces bounded conversion functions.

## Affected products

- GNU LibreDWG up to 0.14

## Timeline

- 2026-05-25: advisory: Initial disclosure by VulDB
- 2026-05-25: disclosed
- 2026-05-25: patched: Patch commit be996bf2178a40e98720f18c2414815d244413db released

## References

- [https://github.com/HackC0der/CVE-Repos/blob/main/libredwg/libredwg_6d6a339_heap_overflow_bit_convert_TU.dwg](https://github.com/HackC0der/CVE-Repos/blob/main/libredwg/libredwg_6d6a339_heap_overflow_bit_convert_TU.dwg)
- [https://github.com/LibreDWG/libredwg/commit/be996bf2178a40e98720f18c2414815d244413db](https://github.com/LibreDWG/libredwg/commit/be996bf2178a40e98720f18c2414815d244413db)
- [https://github.com/LibreDWG/libredwg/issues/1246](https://github.com/LibreDWG/libredwg/issues/1246)
- [https://vuldb.com/submit/814261](https://vuldb.com/submit/814261)
- [https://vuldb.com/vuln/365486](https://vuldb.com/vuln/365486)
- [https://vuldb.com/vuln/365486/cti](https://vuldb.com/vuln/365486/cti)
- [https://www.gnu.org/](https://www.gnu.org/)

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