# CVE-2026-116737: libphdi through 20260902 Heap Out-of-Bounds Read via Extent Data File Path

Status: published. Published: 2026-10-26. Updated: 2026-11-02.

libphdi through 20260902 contains a heap out-of-bounds read vulnerability in libphdi_data_files_get_extent_data_file_path that uses the directory prefix length instead of the basename length. Attackers can supply a crafted Parallels disk image descriptor with a long directory prefix and short basename to crash the process or expose adjacent heap memory.

## Remediation

- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: VulnCheck) — https://github.com/libyal/libphdi/commit/61e3e1f6b4c5e15ce827b11858ba51f0dba254e3

## Affected products and versions

- libyal / libphdi (libyal/libphdi): ≥ 0; ≤ 20260902 (affected, custom). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 6.9 (medium); CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 6.1 (medium); CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H; source: CNA: VulnCheck

- CISA KEV: No listing in collected sources

- EPSS: 0.13% as of 2026-11-02; percentile 2.24%

- SSVC: exploitation poc; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-131

## Exploit evidence

- exploit: https://hackmd.io/@haindpwn/cve-2026-116737-libphdi-extent-data-file-path-heap-oob-read (ADP: CISA-ADP)

## References

- https://github.com/libyal/libphdi/issues/6 (CNA: VulnCheck; issue-tracking)

- https://github.com/libyal/libphdi (CNA: VulnCheck; product)

- https://github.com/libyal/libphdi/commit/61e3e1f6b4c5e15ce827b11858ba51f0dba254e3 (CNA: VulnCheck; patch)

- https://github.com/libyal/libphdi/blob/20260902/libphdi/libphdi_data_files.c#L890-L907 (CNA: VulnCheck; technical-description)

- https://hackmd.io/@haindpwn/libphdi-extent-data-file-path-heap-oob-read (CNA: VulnCheck; third-party-advisory)

- https://www.vulncheck.com/advisories/libphdi-through-20260902-heap-out-of-bounds-read-via-extent-data-file-path (CNA: VulnCheck; third-party-advisory)

- https://hackmd.io/@haindpwn/cve-2026-116737-libphdi-extent-data-file-path-heap-oob-read (ADP: CISA-ADP; exploit)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-116737; retrieved 2026-11-02; source updated 2026-11-02

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-116737; retrieved 2026-11-02; source updated Not reported

Revision: 98f23893a2b3f643b0017c3bdf3803bead3161879f09a1040bf57ec8edb53156

Canonical: https://y2.dev/cve/CVE-2026-116737

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