{"id":"GHSA-24qx-w28j-9m6p","summary":"Jupyter Server has a  CORS Origin Validation Bypass via `re.match()` in `allow_origin_pat`","details":"Jupyter Server uses `re.match()` to validate the Origin header against the `allow_origin_pat` configuration.\n\nSince `re.match()` only anchors at the start of the string, an attacker who controls a domain like `http://trusted.example.com.evil.com/` passes validation against a pattern intended to match only `trusted.example.com`.\n\n### Impact\n\n\u003c=2.17.0\n\n### Patches\n\n057869a327c46730afede3eab0ca2d2e3e74acea, 49b34392feaa97735b3b777e3baf8f22f2a14ed8 \n\n### Workarounds\n\nWrap your `allow_origin_pat` value with `^` and `$`\n\n### References\n\nhttps://github.com/jupyter-server/jupyter_server/pull/603\nhttps://docs.python.org/3/library/re.html#re.fullmatch\nhttps://docs.python.org/3/library/re.html#re.match","aliases":["CVE-2026-40110","PYSEC-2026-2187"],"modified":"2026-07-31T20:30:09.665751200Z","published":"2026-05-05T16:54:31Z","database_specific":{"cwe_ids":["CWE-625","CWE-777"],"severity":"HIGH","github_reviewed":true,"github_reviewed_at":"2026-05-05T16:54:31Z","nvd_published_at":"2026-05-05T22:16:00Z"},"references":[{"type":"WEB","url":"https://github.com/jupyter-server/jupyter_server/security/advisories/GHSA-24qx-w28j-9m6p"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-40110"},{"type":"WEB","url":"https://github.com/jupyter-server/jupyter_server/pull/603"},{"type":"WEB","url":"https://github.com/jupyter-server/jupyter_server/commit/057869a327c46730afede3eab0ca2d2e3e74acea"},{"type":"WEB","url":"https://github.com/jupyter-server/jupyter_server/commit/49b34392feaa97735b3b777e3baf8f22f2a14ed8"},{"type":"WEB","url":"https://access.redhat.com/errata/RHSA-2026:43038"},{"type":"WEB","url":"https://access.redhat.com/security/cve/CVE-2026-40110"},{"type":"WEB","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2466912"},{"type":"PACKAGE","url":"https://github.com/jupyter-server/jupyter_server"},{"type":"WEB","url":"https://github.com/pypa/advisory-database/tree/main/vulns/jupyter-server/PYSEC-2026-2187.yaml"},{"type":"WEB","url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-40110.json"}],"affected":[{"package":{"name":"jupyter-server","ecosystem":"PyPI","purl":"pkg:pypi/jupyter-server"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.18.0"}]}],"versions":["0.0.0","0.0.1","0.0.2","0.0.3","0.0.4","0.0.5","0.1.0","0.1.1","0.2.0","0.2.1","0.3.0","1.0.0","1.0.0rc0","1.0.0rc1","1.0.0rc10","1.0.0rc11","1.0.0rc12","1.0.0rc13","1.0.0rc14","1.0.0rc15","1.0.0rc16","1.0.0rc2","1.0.0rc3","1.0.0rc4","1.0.0rc5","1.0.0rc6","1.0.0rc7","1.0.0rc8","1.0.0rc9","1.0.1","1.0.10","1.0.11","1.0.2","1.0.3","1.0.4","1.0.5","1.0.6","1.0.7","1.0.8","1.0.9","1.1.0","1.1.1","1.1.2","1.1.3","1.1.4","1.10.0","1.10.1","1.10.2","1.11.0","1.11.1","1.11.2","1.12.0","1.12.1","1.13.0","1.13.1","1.13.2","1.13.3","1.13.4","1.13.5","1.15.0","1.15.1","1.15.2","1.15.3","1.15.4","1.15.5","1.15.6","1.16.0","1.17.0","1.17.1","1.18.0","1.18.1","1.19.0","1.19.1","1.2.0","1.2.1","1.2.2","1.2.3","1.21.0","1.23.0","1.23.1","1.23.2","1.23.3","1.23.4","1.23.5","1.23.6","1.24.0","1.3.0","1.4.0","1.4.1","1.5.0","1.5.1","1.6.0","1.6.1","1.6.2","1.6.3","1.6.4","1.7.0","1.7.0a1","1.7.0a2","1.8.0","1.9.0","2.0.0","2.0.0a0","2.0.0a1","2.0.0a2","2.0.0b0","2.0.0b1","2.0.0rc0","2.0.0rc1","2.0.0rc2","2.0.0rc3","2.0.0rc4","2.0.0rc5","2.0.0rc6","2.0.0rc7","2.0.0rc8","2.0.1","2.0.2","2.0.3","2.0.4","2.0.5","2.0.6","2.0.7","2.1.0","2.10.0","2.10.1","2.11.0","2.11.1","2.11.2","2.12.0","2.12.1","2.12.2","2.12.3","2.12.4","2.12.5","2.13.0","2.14.0","2.14.1","2.14.2","2.15.0","2.16.0","2.17.0","2.2.0","2.2.1","2.3.0","2.4.0","2.5.0","2.6.0","2.7.0","2.7.1","2.7.2","2.7.3","2.8.0","2.9.0","2.9.1"],"database_specific":{"last_known_affected_version_range":"\u003c= 2.17.0","source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-24qx-w28j-9m6p/GHSA-24qx-w28j-9m6p.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:L/SC:L/SI:L/SA:L"}]}