CVE-2021-25786 Use after free in n/a

Medium 5.3 Published 11 Aug 2023 Updated 9 Oct 2024

Remote attackers can execute arbitrary code via a crafted PDF file exploiting a use-after-free vulnerability in the QPDF library.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Local or same network only
Victim action needed: A user has to click or open something
Fix: Available

What is CVE-2021-25786?

CVE-2021-25786 is a medium-severity use after free vulnerability in n/a, published on 11 Aug 2023. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

Official description

An issue was discovered in QPDF version 10.0.4, allows remote attackers to execute arbitrary code via crafted .pdf file to Pl_ASCII85Decoder::write parameter in libqpdf.

Weakness: CWE-416

Which versions are affected by CVE-2021-25786?

It affects 1 product.

Products include Qpdf Project Qpdf.

How do I fix CVE-2021-25786?

Upgrade to a fixed version.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2021-25786 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-25786 exists.

Sources

Also known as DEBIAN-CVE-2021-25786, GHSA-f3pg-6m52-2j62, OESA-2023-1542, UBUNTU-CVE-2021-25786.