The flaw lies in a class‑decoding loop within the R13‑R2000 DWG parser of LibreDWG. The loop calls realloc on every iteration without limiting the number of classes. An attacker can supply a specially crafted DWG file that forces the loop to perform an extreme number of reallocations, draining system memory and causing the parser to become unresponsive. The consequence is a denial of service that affects any application using the vulnerable library to read such a file. This weakness is classified as resource exhaustion and is reflected by the CWE identifiers for unsanitized input and unchecked growth.

All versions of LibreDWG libredwg released before 0.14 are affected. The problem is present in the free C library before the 0.14 tag and has been corrected starting with that release. Applications that link against older versions of libredwg and parse R13‑R2000 DWG files are susceptible.

The severity of the vulnerability is moderate with a CVSS score of 5.5. No EPSS data is available, and the issue is not listed in the CISA KEV catalog. The attack vector is inferred to be local: an attacker who can supply a crafted DWG file to the application or service that uses libredwg can trigger the denial of service. Since the flaw causes resource exhaustion, it requires the target process to be running; it does not provide an escalation or remote code execution pathway. The exploitation likelihood is therefore limited to scenarios where untrusted files are processed.