CURL-CVE-2018-1000120
- Source
- https://curl.se/docs/CVE-2018-1000120.html
- Import Source
- https://curl.se/docs/CURL-CVE-2018-1000120.json
- JSON Data
- https://api.osv.dev/v1/vulns/CURL-CVE-2018-1000120
- Aliases
- Published
- 2018-03-14T08:00:00Z
- Modified
- 2024-06-07T13:53:51Z
- Summary
- FTP path trickery leads to NIL byte out of bounds write
- Details
-
curl can be fooled into writing a zero byte out of bounds.
This bug can trigger when curl is told to work on an FTP URL, with the setting to only issue a single CWD command (
--ftp-method singlecwdor the libcurl alternativeCURLOPT_FTP_FILEMETHOD).curl then URL-decodes the given path, calls strlen() on the result and deducts the length of the filename part to find the end of the directory within the buffer. It then writes a zero byte on that index, in a buffer allocated on the heap.
If the directory part of the URL contains a "%00" sequence, the directory length might end up shorter than the filename path, making the calculation
size_t index = directory_len - filepart_lenend up with a huge index variable for where the zero byte gets stored:heap_buffer[index] = 0. On several architectures that huge index wraps and works as a negative value, thus overwriting memory before the intended heap buffer.By using different file part lengths and putting %00 in different places in the URL, an attacker that can control what paths a curl-using application uses can write that zero byte on different indexes.
- References
-
- Credits
-
-
- Duy Phan Thanh - FINDER
-
- Daniel Stenberg - REMEDIATION_DEVELOPER
-
Affected packages
Git / github.com/curl/curl.git
Affected ranges
- Type
- SEMVER
- Events
-
Introduced7.12.3Fixed7.59.0
- Type
- GIT
- Repo
- https://github.com/curl/curl.git
- Events