CVE-2025-57807
imagemagick: ImageMagick BlobStream Forward-Seek Under-Allocation
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · September 6, 2025
Updated · September 23, 2026
Description
A heap based out of bounds write flaw has been discovered in ImageMagick. For memory-backed blobs SeekBlob() permits advancing the stream offset beyond the current end without increasing capacity. The subsequent WriteBlob() then expands by quantum + length (amortized) instead of offset + length, and copies to data + offset. When offset ≫ extent, the copy targets memory beyond the allocation, producing a deterministic heap write on 64-bit builds.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
CVSS / CWE
CVSS 3.1 · 4.2CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:L
CWE-787 · Out-of-bounds Write