libheif is a HEIF and AVIF file format decoder and encoder. The fix for CVE-2026-3949 (commit `b97c8b5`, PR #1712) introduced an integer overflow in the very security check it added. The check itself can be bypassed, allowing a crafted HEIF file with a VVC track to trigger the same out-of-bounds heap read that CVE-2026-3949 was meant to prevent. This is a separate, currently-unpatched vulnerability. Issue #1712 was closed as fixed without testing the edge case where `size` is near `UINT32_MAX`.
libheif is a HEIF and AVIF file format decoder and encoder. The fix for CVE-2026-3949 (commit b97c8b5, PR #1712) introduced an integer overflow in the very security check it added. The check itself can be bypassed, allowing a crafted HEIF file with a VVC track to trigger the same out-of-bounds heap read that CVE-2026-3949 was meant to prevent. This is a separate, currently-unpatched vulnerability. Issue #1712 was closed as fixed without testing the edge case where size is near UINT32_MAX. Version 1.22.0 patches the issue.
Why this VPI (explainable, experimental)
VPI breakdown
| Impact | 68.00 |
| Exploitation signal(No additional exploitation signal) | ×1.00 |
| VPI | 68.00 |
VPI formula vpi-v1