{"id":"CVE-2024-21645","aliases":["GHSA-ghmw-rwh8-6qmr","PYSEC-2026-1818"],"url":"https://o3.security/vulnerability/CVE-2024-21645","summary":"pyLoad Log Injection","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","published":"2024-01-08T13:20:47.181Z","modified":"2026-10-28T02:31:09.810260612Z","cvss":{"score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"},"epss":{"score":0.24513,"percentile":0.97755,"asOf":"2026-08-23"},"cisaKev":null,"exploitsKnown":1,"affectedPackages":[{"ecosystem":"PyPI","name":"pyload-ng","fixedVersion":"0.5.0b3.dev77"}],"fix":{"url":"https://github.com/pyload/pyload/commit/4159a1191ec4fe6d927e57a9c4bb8f54e16c381d","label":"pyload/pyload@4159a11"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/21xxx/CVE-2024-21645.json"},{"type":"ADVISORY","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":"FIX","url":"https://github.com/pyload/pyload/commit/4159a1191ec4fe6d927e57a9c4bb8f54e16c381d"},{"type":"PACKAGE","url":"https://github.com/pyload/pyload"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-28T02:31:09.810260612Z"}}