Out-of-bounds Read in Microsoft Heif_image_extension
CVE-2025-62821
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 com…
Vulnerability class: Buffer Overflow
EPSS: 0.011 (60.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H.
Affected products
- Microsoft Heif_image_extension — versions 1.2.22.0
- N/a — versions n/a
Weakness classification (CWE)
Public proof-of-concept exploits
References
- cve@mitre.org (Exploit, Third Party Advisory)
Frequently asked questions
- What is CVE-2025-62821?
- CVE-2025-62821 is a critical-severity vulnerability in Microsoft Heif_image_extension, classified under Out-of-bounds Read. CVSS score: 9.1/10. Published 2026-06-19.
- How severe is CVE-2025-62821?
- Critical severity. CVSS v3 base score is 9.1 out of 10.
- Is CVE-2025-62821 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.