LibreDWG is a free C library to read and write DWG files. Prior to 0.14, a specially crafted R13-R2000 DWG can trigger algorithmic resource exhaustion in `decode_R13_R2000` in `src/decode.c`. The class-decoding loop performs `realloc` on every iteration without a sanity check on `num_classes`.
Manipulating that field forces an extremely slow allocation loop and denial of service when the file is parsed. Running the parser in a sandbox with memory limits is a workaround rather than a remediation. This issue is fixed in version 0.14.
Attack Parameters
Attack Vector
Local
Requires local access
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
Required
User action required
Impact Assessment
Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
High
Complete denial of service
CVSS Vector v3.1
Weakness Type (CWE)
Vulnerable Products
libredwg:libredwg
References 4
https://github.com/LibreDWG/libredwg/security/advisories/GHSA-gp83-hcvh-g255
https://github.com/LibreDWG/libredwg/security/advisories/GHSA-gp83-hcvh-g255
https://github.com/LibreDWG/libredwg/issues/1261
https://github.com/LibreDWG/libredwg/issues/1261
https://github.com/LibreDWG/libredwg/commit/9de893a2e395ff5ac104a46cca54c5e2cf8…
https://github.com/LibreDWG/libredwg/commit/9de893a2e395ff5ac104a46cca54c5e2cf8f02cf
https://github.com/LibreDWG/libredwg/releases/tag/0.14
https://github.com/LibreDWG/libredwg/releases/tag/0.14