CVE-2025-62171

ImageMagick is an open source software suite for displaying, converting, and editing raster image files. In ImageMagick versions prior to 7.1.2-7 and 6.9.13-32, an integer overflow vulnerability exists in the BMP decoder on 32-bit systems. The vulnerability occurs in coders/bmp.c when calculating the extent value by multiplying image columns by bits per pixel. On 32-bit systems with size_t of 4 bytes, a malicious BMP file with specific dimensions can cause this multiplication to overflow and wrap to zero. The overflow check added to address CVE-2025-57803 is placed after the overflow occurs, making it ineffective. A specially crafted 58-byte BMP file with width set to 536,870,912 and 32 bits per pixel can trigger this overflow, causing the bytes_per_line calculation to become zero. This vulnerability only affects 32-bit builds of ImageMagick where default resource limits for width, height, and area have been manually increased beyond their defaults. 64-bit systems with size_t of 8 bytes are not vulnerable, and systems using default ImageMagick resource limits are not vulnerable. The vulnerability is fixed in versions 7.1.2-7 and 6.9.13-32.

Weakness

The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.

Affected Software

Potential Mitigations

• Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
• If possible, choose a language or compiler that performs automatic bounds checking.
• Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482].
• Use libraries or frameworks that make it easier to handle numbers without unexpected consequences.
• Examples include safe integer handling packages such as SafeInt (C++) or IntegerLib (C or C++). [REF-106]
• Perform input validation on any numeric input by ensuring that it is within the expected range. Enforce that the input meets both the minimum and maximum requirements for the expected range.
• Use unsigned integers where possible. This makes it easier to perform validation for integer overflows. When signed integers are required, ensure that the range check includes minimum values as well as maximum values.
• Understand the programming language’s underlying representation and how it interacts with numeric calculation (CWE-681). Pay close attention to byte size discrepancies, precision, signed/unsigned distinctions, truncation, conversion and casting between types, “not-a-number” calculations, and how the language handles numbers that are too large or too small for its underlying representation. [REF-7]
• Also be careful to account for 32-bit, 64-bit, and other potential differences that may affect the numeric representation.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/92.html

References

• https://github.com/ImageMagick/ImageMagick/commit/cea1693e2ded51b4cc91c70c54096cbed1691c00
• https://github.com/ImageMagick/ImageMagick/security/advisories/GHSA-9pp9-cfwx-54rm
• https://lists.debian.org/debian-lts-announce/2025/10/msg00019.html