CVE-2025-62821: Microsoft Heif Image Extension

Critical severity, CVSS 9.1. EPSS: 1.1% chance of exploitation in the next 30 days.

Microsoft HEIF Image Extensions 1.2.22.0 has an out-of-bounds read because CHEIFItemInfoEntry_GetDataSize can return success while leaving the reported data size as 0. This causes a caller to make a 1-byte allocation. Later, CopyPixels computes copy_size = stride * abs(roi_height) but does not check the source buffer length before a memmove call.

Affected products

• Microsoft Heif Image Extension: version 1.2.22.0 only

Published 2026-06-19. Last modified 2026-10-05.