{"id":"CVE-2026-34730","aliases":["GHSA-hgjq-p8cr-gg4h","PYSEC-2026-2135"],"url":"https://o3.security/vulnerability/CVE-2026-34730","summary":"Copier `_external_data` allows path traversal and absolute-path local file read without unsafe mode","details":"Copier is a library and CLI app for rendering project templates. Prior to version 9.14.1, Copier's _external_data feature allows a template to load YAML files using template-controlled paths. If untrusted templates are in scope, a malicious template can read attacker-chosen YAML-parseable local files that are accessible to the user running Copier and expose their contents in rendered output. This issue has been patched in version 9.14.1.","published":"2026-04-02T18:09:16.007Z","modified":"2026-08-07T11:50:58.209872457Z","cvss":{"score":5.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"PyPI","name":"copier","fixedVersion":"9.14.1"}],"fix":{"url":"https://github.com/copier-org/copier/commit/5413062eb17b73dc885f5e645cdc161e69ef641b","label":"copier-org/copier@5413062"},"references":[{"type":"WEB","url":"https://github.com/copier-org/copier/releases/tag/v9.14.1"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34730.json"},{"type":"ADVISORY","url":"https://github.com/copier-org/copier/security/advisories/GHSA-hgjq-p8cr-gg4h"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-34730"},{"type":"FIX","url":"https://github.com/copier-org/copier/commit/5413062eb17b73dc885f5e645cdc161e69ef641b"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-07T11:50:58.209872457Z"}}