RCE in Mithaldu Pdf::webkit

CVE-2026-17431

PDF::WebKit versions through 1.2 for Perl allow OS command injection via a 2-arg open() of the output path in to_pdf and of stylesheet paths in _style_tag_for. to_pdf reads the generated PDF back from its path argument, and _style_tag_for reads each entry of the stylesheets list, by assigning the path to a local @ARGV and reading it with the diamond operator, which opens each @ARGV element with Perl's 2-arg open(). A value that begins or ends with a pipe ("| cmd", "cmd |") is run as a command rather than opened as a file, and one that begins with a redirect ("> path", ">> path") opens that path for write or append. to_file forwards its path argument to to_pdf and reaches the same read. Any caller that forwards untrusted input as the output path or as a stylesheets entry can run a command under the process UID; with the "cmd |" form the command's output is returned in place of the PDF, and with the "> path" form the named file is truncated. Stylesheets may only be added to an HTML source, so a URL or file source exposes the output path alone.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:N.

EPSS exploit prediction

EPSS: 0.009 (59.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 60th percentile — 59.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-17431: held from 0.006 to 0.009.

EPSS over last 30 days · oldest: 0.006 · newest: 0.009 · change: +0.004

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-17431?
CVE-2026-17431 is a medium-severity vulnerability in Mithaldu Pdf::webkit, classified under External Control of File Name or Path. CVSS score: 6.1/10. Published 2026-08-13.
How severe is CVE-2026-17431?
Medium severity. CVSS v3 base score is 6.1 out of 10.