CVE-2026-34726: Copier is a library and CLI app for rendering project templates

Routine

MEDIUM 4.4UPGRADE

CVE-2026-34726 is a medium-severity flaw (CVSS 4.4) affecting copier. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Copier is a library and CLI app for rendering project templates. Prior to version 9.14.1, Copier's _subdirectory setting is documented as the subdirectory to use as the template root. However, the current implementation accepts parent-directory traversal such as .. and uses it directly when selecting the template root. As a result, a template can escape its own directory and make Copier render files from the parent directory without --UNSAFE. Thi

Why this priority

Public exploit reference

A fixed release or distro patch exists.

Risk facts

CVSS score	4.4 (Medium)
Attack vector	Local
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	0.4% (top 68%)
CISA exploited list	No
Weakness	CWE-22
Published	2026-04-02
Last modified	2026-07-24

Publisher (CNA): GitHub, Inc. · Vendor: copier-org

Last updated 2026-07-24 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-04-02 19:21 UTCPublished CVE record published
2026-07-24 21:10 UTCUpdated Record last modified

copier-org copier UPGRADE

Affected: < 9.14.1

Fixed in: 9.14.1

Safe to downgrade to: no unaffected older release

1. Check installed version

pip show copier

2. UPGRADE to 9.14.1

pip install --upgrade "copier>=9.14.1"

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-34726?

copier: upgrade to 9.14.1. Exact commands for each OS are on this page.

Is CVE-2026-34726 being exploited?

CVE-2026-34726 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-34726 affect?

CVE-2026-34726 affects copier. Severity is medium (CVSS 4.4). Copier is a library and CLI app for rendering project templates. Prior to version 9.14.1, Copier's _subdirectory setting is documented as the subdirectory to use as the template root. However, the current implementation accepts parent-direc

How urgent is CVE-2026-34726?

Priority 28/100. Public exploit reference

Related CVEs

CVE-2026-34730 MEDIUM 5.5 UPGRADE Copier is a library and CLI app for rendering project templates

References

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