# CVE-2026-111135: libfwsi heap out-of-bounds read in MTP volume parsing

Source: https://junglewise.ai/threats/cve-2026-111135-libfwsi-through-20260522-contains-a-heap-out-of-bounds-read  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-15. Updated: 2026-10-16  
License: CC BY 4.0 with a link back

CVE-2026-111135 · Severity: medium · CVSS 6.1 · Published 2026-10-15

libfwsi is a library that reads Windows Shell Item format data found in shortcut files, jump lists, and shell bags. A heap out-of-bounds read vulnerability allows attackers to crash applications that use libfwsi by embedding specially crafted MTP volume shell items in these files, potentially exposing sensitive memory contents.

Vendors: [Libyal](https://junglewise.ai/threats/vendors/libyal).

## Quick answers

**Is CVE-2026-111135 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-111135 being exploited in the wild.

**How severe is CVE-2026-111135?** Medium severity, with a CVSS score of 6.1, published 15 October 2026.

**Which products and versions are affected?** Libyal Libfwsi through 20260522.

**Is there a fix for CVE-2026-111135?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-111135 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-111135?** Check whether you run Libyal Libfwsi 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

The vulnerability is a heap out-of-bounds read in the libfwsi_mtp_volume_values_read_data() function triggered by crafted MTP volume shell items with a data size of 44 bytes or more but an item size between 10 and 53 bytes. Attackers can embed these malformed items in .lnk files, jump lists, or shell bags to read past buffer bounds. Exploitation requires the victim to open or process a file containing the malicious item.

## Affected products

- libyal libfwsi through 20260522

## Timeline

- 2026-10-15: disclosed

## References

- [https://github.com/](https://github.com/)
- [https://github.com/libyal/libfwsi](https://github.com/libyal/libfwsi)

## Related threats

- [libfwsi heap out-of-bounds read in MTP file entry parsing](https://junglewise.ai/threats/cve-2026-111134-libfwsi-through-20260522-contains-a-heap-out-of-bounds-read)