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. Starting in version 1.13...

Description

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 command and disallow PDF output and the `--extract-media` option.

Metrics

CVSS 3.1

5/10

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

EPSS Probability

0.35%

26.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-20

Affected Software

Vendor	Product	Versions
Pandoc	Pandoc	>= 1.13, < 3.1.4
Debian	Debian Linux	10.0

References

Timeline

Published: Jul 5, 2023
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is 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. 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 command and disallow PDF output and the `--extract-media` option.

How severe is CVE-2023-35936?

CVE-2023-35936 has a CVSS score of 5/10 (MEDIUM severity). The EPSS model estimates a 0.35% probability of exploitation in the next 30 days.

How do I fix CVE-2023-35936?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.