CVE-2026-53951

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Source

https://cve.org/CVERecord?id=CVE-2026-53951

Import Source

https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53951.json

JSON Data

https://api.osv.dev/v1/vulns/CVE-2026-53951

Aliases

Published

2026-07-08T15:26:08Z

Modified

2026-10-28T02:30:52Z

Severity

8.8 (High) CVSS_V4 - CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H CVSS Calculator

Summary

Copier: trust-prefix bypass via path traversal runs tasks unprompted

Details

Copier is a library and CLI app for rendering project templates. In versions 9.5.0 through 9.15.1, the trust setting's prefix match (copier/_settings.py) compares the template URL against a trusted prefix with a raw str.startswith and no path normalization, while the URL is normalized when the template is actually fetched (Path.resolve() for local paths; libcurl dot-segment removal for https). A template reference that textually starts with a trusted prefix but contains .. is therefore granted trust yet resolves to a different, attacker-controlled template, whose tasks / migrations / jinja_extensions then run without the --trust prompt — arbitrary command execution. Version 9.15.2 patches the issue.

Database specific

{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-22",
        "CWE-94"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53951.json"
}

References

Affected packages

Git / github.com/copier-org/copier

Affected ranges

Type

GIT

Repo

https://github.com/copier-org/copier

Events

Introduced

d735c8beac8307c06d9c881714328b76711a4b4d

Fixed

a90729e8b828ccfdd4e066696044ac20a85be81c

Database specific

Show details

{
    "extracted_events": [
        {
            "range": [
                {
                    "introduced": "9.5.0"
                },
                {
                    "fixed": "9.15.2"
                }
            ],
            "source": "AFFECTED_FIELD",
            "strategy": "StringRangeExpression"
        },
        {
            "original_tag": "v9.15.2",
            "range": [
                {
                    "fixed": "a90729e8b828ccfdd4e066696044ac20a85be81c"
                }
            ],
            "source": "REFERENCES_TAG"
        }
    ]
}

Affected versions

v9.*

v9.10.0

v9.10.1

v9.10.2

v9.10.3

v9.11.0

v9.11.1

v9.11.2

v9.11.3

v9.12.0

v9.13.0

v9.13.1

v9.14.0

v9.14.1

v9.14.2

v9.14.3

v9.15.0

v9.15.1

v9.5.0

v9.6.0

v9.7.0

v9.7.1

v9.8.0

v9.9.0

v9.9.1

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53951.json"