alhudz opened a new pull request, #476:
URL: https://github.com/apache/commons-fileupload/pull/476
`Repro:` `Content-Disposition: attachment;
filename="=?utf-8?b?ZXZpbC5leGU=?="`, a valid RFC 2047 encoded-word that uses
the lower-case `b` marker.
`Expected:` the filename decodes to `evil.exe`, matching the upper-case
`=?utf-8?B?...?=` form.
`Actual:` `MimeUtils.decodeWord` throws `UnsupportedEncodingException`, so
`ParameterParser` keeps the raw value `=?utf-8?b?ZXZpbC5leGU=?=`. Lower-case
`q` behaves the same way against the `Q` marker.
`Cause:` the charset token is lower-cased before use, but the encoding token
is compared case-sensitively with `encoding.equals("B")` / `equals("Q")`. RFC
2047 section 2 defines the encoding as case-independent (`b` == `B`, `q` ==
`Q`).
`Fix:` compare the encoding token with `equalsIgnoreCase`, so `b`/`q` decode
identically to `B`/`Q`. Two regression tests cover the lower-case base64 and
quoted-printable markers; both fail before the change.
- [x] Read the [contribution guidelines](CONTRIBUTING.md) for this project.
- [ ] Read the [ASF Generative Tooling
Guidance](https://www.apache.org/legal/generative-tooling.html) if you use
Artificial Intelligence (AI).
- [ ] I used AI to create any part of, or all of, this pull request. Which
AI tool was used to create this pull request, and to what extent did it
contribute?
- [x] Run a successful build using the default
[Maven](https://maven.apache.org/) goal with `mvn`; that's `mvn` on the command
line by itself.
- [x] Write unit tests that match behavioral changes, where the tests fail
if the changes to the runtime are not applied. This may not always be possible,
but it is a best practice.
- [x] Write a pull request description that is detailed enough to understand
what the pull request does, how, and why.
- [x] Each commit in the pull request should have a meaningful subject line
and body. Note that a maintainer may squash commits during the merge process.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
