CVE-2026-73639

[CVE catalog]

Severity

Critical · CVSS 9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Published

Sep 17, 2026, 10:17:03 PM UTC

Source

[NVD] · [CVE record]

EPSS

0.70% · Oct 25, 2026

Imager::File::PNG versions from 1.003 before 1.004 for Perl write past the end of the row buffer reading a PNG with a tRNS transparency chunk in read_direct8. With a tRNS chunk, read_direct8() adds an alpha channel to the image it creates but still sizes the row buffer from the original channel count. libpng expands the transparency into that extra channel, so png_read_row() fills one channel more than the buffer holds, at one byte per sample, and writes width bytes past the end of the allocation. Palette images go to read_paletted() and 16-bit images to read_direct16(), which sizes its buffer from png_get_rowbytes() and allocates enough for the expanded row. The same reader ships bundled in the Imager distribution. Reading an attacker-supplied PNG through Imager->read() corrupts the heap, which can crash the process.