User-controlled data URLs parsed by urllib.request.DataHandler allow injecting headers through newlines in the data URL mediatype.
Weakness
The product uses CRLF (carriage return line feeds) as a special element, e.g. to separate lines or records, but it does not neutralize or incorrectly neutralizes CRLF sequences from inputs.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Python3.10 | Ubuntu | jammy | * |
| Python3.11 | Ubuntu | esm-apps/jammy | * |
| Python3.11 | Ubuntu | jammy | * |
| Python3.12 | Ubuntu | noble | * |
| Python3.13 | Ubuntu | questing | * |
| Python3.14 | Ubuntu | questing | * |
| Python3.4 | Ubuntu | esm-infra-legacy/trusty | * |
| Python3.5 | Ubuntu | esm-infra-legacy/trusty | * |
| Python3.5 | Ubuntu | esm-infra/xenial | * |
| Python3.6 | Ubuntu | esm-infra/bionic | * |
| Python3.7 | Ubuntu | esm-apps/bionic | * |
| Python3.8 | Ubuntu | esm-apps/bionic | * |
| Python3.8 | Ubuntu | esm-infra/focal | * |
| Python3.9 | Ubuntu | esm-apps/focal | * |
Potential Mitigations
Related Attack Patterns
References
- https://github.com/python/cpython/commit/05356b1cc153108aaf27f3b72ce438af4aa218c0
- https://github.com/python/cpython/commit/34d76b00dabde81a793bd06dd8ecb057838c4b38
- https://github.com/python/cpython/commit/3f396ca9d7bbe2a50ea6b8c9b27c0082884d9f80
- https://github.com/python/cpython/commit/4ed11d3cd288e6b90196a15c5a825a45d318fe47
- https://github.com/python/cpython/commit/a35ca3be5842505dab74dc0b90b89cde0405017a
- https://github.com/python/cpython/commit/f25509e78e8be6ea73c811ac2b8c928c28841b9f
- https://github.com/python/cpython/issues/143925
- https://github.com/python/cpython/pull/143926
- https://mail.python.org/archives/list/security-announce@python.org/thread/X66HL7SISGJT33J53OHXMZT4DFLMHVKF/