{"id":"PYSEC-2026-1818","summary":"pyload Log Injection vulnerability","details":"### Summary\nA log injection vulnerability was identified in `pyload`. This vulnerability allows any unauthenticated actor to inject arbitrary messages into the logs gathered by `pyload`.\n\n### Details\n`pyload` will generate a log entry when attempting to sign in with faulty credentials. This entry will be in the form of `Login failed for user 'USERNAME'`. However, when supplied with a username containing a newline, this newline is not properly escaped. Newlines are also the delimiter between log entries. This allows the attacker to inject new log entries into the log file.\n\n### PoC\nRun `pyload` in the default configuration by running the following command\n```\npyload\n```\n\nWe can now sign in as the pyload user and view the logs at `http://localhost:8000/logs`.\n![Viewing the logs](https://user-images.githubusercontent.com/44903767/294433796-f2c96e39-8000-4649-99bb-9c50e786243d.png)\n\nAny unauthenticated attacker can now make the following request to inject arbitrary logs.\n\n```\ncurl 'http://localhost:8000/login?next=http://localhost:8000/' -X POST -H 'Content-Type: application/x-www-form-urlencoded' --data-raw $'do=login&username=wrong\\'%0a[2024-01-05 02:49:19]  HACKER               PinkDraconian  THIS ENTRY HAS BEEN INJECTED&password=wrong&submit=Login'\n```\n\nIf we now were to look at the logs again, we see that the entry has successfully been injected.\n![PoC2](https://user-images.githubusercontent.com/44903767/294434785-2fc6dce4-3e2c-4da0-8e80-a6bba882f756.png)\n\n### Impact\nForged or otherwise, corrupted log files can be used to cover an attacker’s tracks or even to implicate another party in the commission of a malicious act.\n","aliases":["CVE-2024-21645","GHSA-ghmw-rwh8-6qmr"],"modified":"2026-07-07T17:48:06.239638373Z","published":"2026-07-07T11:45:29.653767Z","references":[{"type":"WEB","url":"https://github.com/pyload/pyload/security/advisories/GHSA-ghmw-rwh8-6qmr"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-21645"},{"type":"WEB","url":"https://github.com/pyload/pyload/commit/4159a1191ec4fe6d927e57a9c4bb8f54e16c381d"},{"type":"PACKAGE","url":"https://github.com/pyload/pyload"},{"type":"PACKAGE","url":"https://pypi.org/project/pyload-ng"},{"type":"ADVISORY","url":"https://github.com/advisories/GHSA-ghmw-rwh8-6qmr"}],"affected":[{"package":{"name":"pyload-ng","ecosystem":"PyPI","purl":"pkg:pypi/pyload-ng"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.5.0b3.dev77"}]}],"versions":["0.5.0a5.dev528","0.5.0a5.dev532","0.5.0a5.dev535","0.5.0a5.dev536","0.5.0a5.dev537","0.5.0a5.dev539","0.5.0a5.dev540","0.5.0a5.dev545","0.5.0a5.dev562","0.5.0a5.dev564","0.5.0a5.dev565","0.5.0a6.dev570","0.5.0a6.dev578","0.5.0a6.dev587","0.5.0a7.dev596","0.5.0a8.dev602","0.5.0a9.dev615","0.5.0a9.dev629","0.5.0a9.dev632","0.5.0a9.dev641","0.5.0a9.dev643","0.5.0a9.dev655","0.5.0a9.dev806","0.5.0b1.dev1","0.5.0b1.dev2","0.5.0b1.dev3","0.5.0b1.dev4","0.5.0b1.dev5","0.5.0b2.dev10","0.5.0b2.dev11","0.5.0b2.dev12","0.5.0b2.dev9","0.5.0b3.dev13","0.5.0b3.dev14","0.5.0b3.dev17","0.5.0b3.dev18","0.5.0b3.dev19","0.5.0b3.dev20","0.5.0b3.dev21","0.5.0b3.dev22","0.5.0b3.dev24","0.5.0b3.dev26","0.5.0b3.dev27","0.5.0b3.dev28","0.5.0b3.dev29","0.5.0b3.dev30","0.5.0b3.dev31","0.5.0b3.dev32","0.5.0b3.dev33","0.5.0b3.dev34","0.5.0b3.dev35","0.5.0b3.dev38","0.5.0b3.dev39","0.5.0b3.dev40","0.5.0b3.dev41","0.5.0b3.dev42","0.5.0b3.dev43","0.5.0b3.dev44","0.5.0b3.dev45","0.5.0b3.dev46","0.5.0b3.dev47","0.5.0b3.dev48","0.5.0b3.dev49","0.5.0b3.dev50","0.5.0b3.dev51","0.5.0b3.dev52","0.5.0b3.dev53","0.5.0b3.dev54","0.5.0b3.dev57","0.5.0b3.dev60","0.5.0b3.dev62","0.5.0b3.dev64","0.5.0b3.dev65","0.5.0b3.dev66","0.5.0b3.dev67","0.5.0b3.dev68","0.5.0b3.dev69","0.5.0b3.dev70","0.5.0b3.dev71","0.5.0b3.dev72","0.5.0b3.dev73","0.5.0b3.dev74","0.5.0b3.dev75","0.5.0b3.dev76"],"database_specific":{"source":"https://github.com/pypa/advisory-database/blob/main/vulns/pyload-ng/PYSEC-2026-1818.yaml"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"}]}