CVE-2018-1000120

Multiple vulnerabilities have been identified in PHOENIX CONTACT AXC F 2152 with firmware versions 1.x

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in cURL ausnutzen, um Dateien zu manipulieren, Daten offenzulegen oder einen Denial of Service zu verursachen.

Ein Angreifer kann mehrere Schwachstellen in Dell Data Protection Advisor ausnutzen, um beliebigen Code auszuführen, einen Denial-of-Service-Zustand zu erzeugen, Sicherheitsmaßnahmen zu umgehen und nicht näher spezifizierte Angriffe zu starten.

curl can be coerced 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 singlecwd or the libcurl alternative [CURLOPT_FTP_FILEMETHOD](https://curl.se/libcurl/c/CURLOPT_FTP_FILEMETHOD.html)). curl then URL-decodes the given path, calls strlen() on the result and deducts the length of the file name 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 file name path, making the calculation `size_t index = directory_len - filepart_len` end up with a huge index variable for where the zero byte gets stored: `heap_buffer[index] = 0`. On several architectures that huge index will wrap and work as a negative value, thus overwriting memory before the intended heap buffer. By using different file part lengths and putting the string `%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.

Successful exploitation of these vulnerabilities could allow an attacker to decrypt passwords, bypass authentication, and deny service to the device. In addition, these vulnerabilities could interact with third-party vulnerabilities to cause other impacts to integrity, confidentiality, and availability.

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 singlecwd` or the libcurl alternative `CURLOPT_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_len` end 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.