CVE-2023-35936: Pandoc is a Haskell library for converting from one markup format to another, and a command-line tool that uses this library.

Pandoc is a Haskell library for converting from one markup format to another, and a command-line tool that uses this library.

Pandoc is a Haskell library for converting from one markup format to another, and a command-line tool that uses this library. Starting in version 1.13 and prior to version 3.1.4, Pandoc is susceptible to an arbitrary file write vulnerability, which can be triggered by providing a specially crafted image element in the input when generating files using the `--extract-media` option or outputting to PDF format. This vulnerability allows an attacker to create or overwrite arbitrary files on the system ,depending on the privileges of the process running pandoc. It only affects systems that pass untrusted user input to pandoc and allow pandoc to be used to produce a PDF or with the `--extract-media` option. The fix is to unescape the percent-encoding prior to checking that the resource is not above the working directory, and prior to extracting the extension. Some code for checking that the path is below the working directory was flawed in a similar way and has also been fixed. Note that the `--sandbox` option, which only affects IO done by readers and writers themselves, does not block this vulnerability. The vulnerability is patched in pandoc 3.1.4. As a workaround, audit the pandoc

Description from the National Vulnerability Database, published by GitHub

What it means for a small business

If your business uses pandoc, install the vendor's update. If you're not sure whether you use it, ask whoever manages your computers.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.37%, higher than 30% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 29, 2026, updated daily.

Check your own setup

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Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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