Critical (9.8). EPSS 1.4% chance of exploitation in the next 30 days.
GD versions before 2.86 for Perl allow OS command injection and file overwrite via a 2-arg open() of filename arguments in _make_filehandle.
GD::Image::_make_filehandle opens a filename argument with Perl's 2-arg open(), so a filename that begins or ends with a pipe ("| cmd", "cmd |") or begins with a redirect ("> path", ">> path") is run as a command or redirect rather than opened as a file. _make_filehandle is the single open path behind every filename-accepting constructor (new, newFromPng, newFromJpeg, and the rest); the in-memory *Data variants do not open a path and are unaffected.
Any caller that forwards untrusted input to one of these constructors as a pathname can run an arbitrary command or truncate a file under the process UID.
Severity
CVSS 3.1
9.8 critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
1.4% chance of exploitation in the next 30 days; higher than 71% of CVEs (scores of 2026-10-31)