CVE-2026-16770 Command injection in PDF::WebKit
Attackers can inject wkhtmltopdf arguments via HTML meta tags to read local files or write to arbitrary paths when rendering untrusted HTML.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-16770?
CVE-2026-16770 is a critical command injection vulnerability in MITHALDU PDF::WebKit, published on 12 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
PDF::WebKit versions through 1.2 for Perl allow argument injection into wkhtmltopdf via meta tags in the source document.
For an HTML string or file source, the constructor collects every <meta name="pdf-webkit-KEY" content="VALUE"> element in the document head through _pdf_webkit_meta_tags and turns each one into a wkhtmltopdf command line option. KEY is normalized to an option name matching --[a-z0-9-]+ but is not checked against an allow list, VALUE is passed through unchanged as the argument that follows it, and a VALUE of "yes" emits the option as a bare flag. BUILD merges the meta derived options last, so they also override the module defaults and the options passed to new. Switches such as --enable-local-file-access and --cookie-jar are reachable this way. The renderer is executed with an argument list rather than a shell command, so this is argument injection and not shell injection.
Any caller that renders untrusted HTML lets the document choose the renderer's options and override those set by the application, including options that read local files into the resulting PDF or write to a chosen path. A URL source is not scanned, and the scan is skipped when XML::LibXML, a recommended dependency, is not installed.
Weakness: CWE-88
Which versions are affected by CVE-2026-16770?
How do I fix CVE-2026-16770?
No fix has been published for CVE-2026-16770 yet. Limit exposure of the affected software until one is available.
Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.
Is CVE-2026-16770 being exploited?
There is no known exploitation of CVE-2026-16770 in the wild and no public exploit code.
Sources
Also known as GHSA-6f7m-6567-58mj.