CVE-2026-90622: GNU libredwg Layer Encoding dwg.spec DWG_TABLE null pointer dereference
A security flaw has been discovered in GNU libredwg 0.13.4. This impacts the function DWGTABLE of the file src/dwg.spec of the component Layer Encoding. Performing a manipulation results in null pointer dereference. The attack needs to be approached locally. The exploit has been released to the public and may be used for attacks. Upgrading to version 0.14 will fix this issue. The patch is named f5b548c4c1697d66c3dabd0f6a49280a14365a3a. The affected component should be upgraded. The FIELDHANDLE macro itself is NULL-safe (emits nullhandle) - only the two raw zeroing assignments added by 27118c40 ("encode: also disable LAYER.material") dereferenced a NULL material handle; the fix restores the file's existing if (obj->style) guard convention for material.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
GNU libredwgto a version that resolves this vulnerability.Fixed in 0.14Patch f5b548c4c1697d66c3dabd0f6a49280a14365a3a - Compensating control
Approach and test the exploit locally, since the attack needs to be approached locally.
Event History
Frequently Asked Questions
Which deployments are exposed to this issue?
GNU libredwg 0.13.4 is identified as affected. The vulnerable code is in Layer Encoding, specifically the DWG_TABLE function in src/dwg.spec.
What access does an attacker need to exploit the flaw?
Exploitation requires local access and low privileges. A manipulation can trigger a null pointer dereference, resulting in an availability impact.
Is exploit code available?
Yes. The exploit has been released publicly and may be used in attacks.
What is the recommended remediation?
Upgrade the affected GNU libredwg component to version 0.14. The documented patch is f5b548c4c1697d66c3dabd0f6a49280a14365a3a.
What code condition causes the crash?
Two raw zeroing assignments introduced for disabling LAYER.material dereference a NULL material handle. The fix restores an existing if (_obj->style) guard convention; the FIELD_HANDLE macro is already NULL-safe.