Description
OpenMcdf is a fully .NET / C# library to manipulate Compound File Binary File Format files, also known as Structured Storage. Prior to version 3.1.3, OpenMcdf does not detect cycles in the directory entry red-black tree of a Compound File Binary (CFB) document. A crafted CFB file with a cycle in the LeftSiblingID / RightSiblingID chain causes Storage.EnumerateEntries() and Storage.OpenStream() to loop indefinitely, consuming the calling thread with no possibility of recovery via try/catch. This issue has been patched in version 3.1.3.
Affected products
openmcdf: openmcdf
References4
- github.com/openmcdf/openmcdf/security/advisories/GHSA-jxpf-xq2m… ExploitVendor Advisory
- github.com/openmcdf/openmcdf/security/advisories/GHSA-jxpf-xq2m… ExploitVendor Advisory
- github.com/openmcdf/openmcdf/commit/24f445a557fc4f46461cf6d02d2… Patch
- github.com/openmcdf/openmcdf/releases/tag/v3.1.3 Release Notes
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 8 · as of 13 November 2026
- CWE
- CWE-835
Could this be exploited in your environment?
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