CVE-2026-53951

See a problem?
Please try reporting it to the source first.
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
2026-08-12T03:51:15Z
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": [
        {
            "introduced": "9.5.0"
        },
        {
            "fixed": "9.15.2"
        }
    ],
    "source": "AFFECTED_FIELD"
}

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"