{"id":"DEBIAN-CVE-2017-11424","details":"In PyJWT 1.5.0 and below the `invalid_strings` check in `HMACAlgorithm.prepare_key` does not account for all PEM encoded public keys. Specifically, the PKCS1 PEM encoded format would be allowed because it is prefaced with the string `-----BEGIN RSA PUBLIC KEY-----` which is not accounted for. This enables symmetric/asymmetric key confusion attacks against users using the PKCS1 PEM encoded public keys, which would allow an attacker to craft JWTs from scratch.","modified":"2026-09-01T20:03:41.622542293Z","published":"2017-08-24T16:29:00.197Z","upstream":["CVE-2017-11424"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2017-11424"}],"affected":[{"package":{"name":"pyjwt","ecosystem":"Debian:12","purl":"pkg:deb/debian/pyjwt?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.2-1.1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2017-11424.json"}},{"package":{"name":"pyjwt","ecosystem":"Debian:13","purl":"pkg:deb/debian/pyjwt?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.2-1.1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2017-11424.json"}},{"package":{"name":"pyjwt","ecosystem":"Debian:14","purl":"pkg:deb/debian/pyjwt?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.2-1.1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2017-11424.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"}]}