USN-7343-2: Jinja2 regression

12 March 2025

USN-7343-1 introduced a regression in Jinja2.

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Releases

Packages

  • jinja2 - small but fast and easy to use stand-alone template engine

Details

USN-7343-1 fixed vulnerabilities in Jinja2. The update introduced a
regression when attempting to import Jinja2 on Ubuntu 18.04 LTS and
Ubuntu 20.04 LTS. This update fixes the problem.

We apologize for the inconvenience.

Original advisory details:

Rafal Krupinski discovered that Jinja2 did not properly restrict
the execution of code in situations where templates are used maliciously.
An attacker with control over a template’s filename and content could
potentially use this issue to enable the execution of arbitrary code.
This issue only affected Ubuntu 14.04 LTS and Ubuntu 16.04 LTS.
(CVE-2024-56201)

It was discovered that Jinja2 sandboxed environments could be escaped
through a call to a string format method. An attacker could possibly use
this issue to enable the execution of arbitrary code. This issue only
affected Ubuntu 14.04 LTS and Ubuntu 16.04 LTS. (CVE-2024-56326)

It was discovered that Jinja2 sandboxed environments could be escaped
through the malicious use of certain filters. An attacker could possibly
use this issue to enable the execution of arbitrary code. (CVE-2025-27516)

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Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

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Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 20.04
Ubuntu 18.04

In general, a standard system update will make all the necessary changes.

References

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