Buffer overflow in Imagemagick

CVE-2020-25674

WriteOnePNGImage() from coders/png.c (the PNG coder) has a for loop with an improper exit condition that can allow an out-of-bounds READ via heap-buffer-overflow. This occurs because it is possible for the colormap to have less than 256 valid values but the loop condition will loop 256 times, attempting to pass invalid colormap data to the event logger. The patch replaces the hardcoded 256 value with a call to MagickMin() to ensure the proper value is used. This could impact application availability when a specially crafted input file is processed by ImageMagick. This flaw affects ImageMagick versions prior to 7.0.8-68.

Vulnerability class: Buffer Overflow

EPSS: 0.010 (59.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2020-25674?
CVE-2020-25674 is a medium-severity vulnerability in Imagemagick, classified under Heap-based Buffer Overflow. CVSS score: 5.5/10. Published 2020-12-08.
How severe is CVE-2020-25674?
Medium severity. CVSS v3 base score is 5.5 out of 10.