GNU wget is vulnerable to denial of service in its FTP OPIE/S-KEY authentication functionality. The server-supplied sequence number from the FTP challenge line is used as an iteration count for an MD5 key-derivation loop without any upper bound validation. A malicious FTP server or a network attacker positioned to intercept FTP traffic can send a crafted OPIE challenge with a sequence number near INT_MAX, causing wget to perform up to approximately 2.1 billion MD5 computations and suspend for some time. The --timeout option does not mitigate this because it applies only to network I/O, not CPU computation.
This issue was fixed in commit e96
GNU Wget does not validate the IP address provided by an FTP PASV response while operating in FTP passive mode. A malicious FTP server, or an HTTP server that redirects to an FTP URL, can exploit this behavior to redirect Wget’s data connection to an arbitrary IP address and port. This allows an attacker to forge server-side requests (SSRF) from the machine running Wget, potentially accessing localhost services or internal network resources.
GNU Wget 1.25.0 Heap Buffer Overflow via HTML Attribute Encoding
GNU Wget through 1.25.0, fixed in commit dd692d9, contains a heap buffer overflow vulnerability in the html_quote_string() function in src/convert.c that allows a remote attacker to trigger memory corruption by supplying a crafted HTML attribute with a large number of characters requiring entity encoding. A server-supplied HTML attribute causes a signed integer counter to overflow during output size accumulation, resulting in an undersized heap allocation and subsequent heap buffer overflow during the copy phase.
GNU Wget 1.25.0 Heap Buffer Overflow via convert_fname() in url.c
GNU Wget through 1.25.0, fixed in commit c2640fe, contains a heap buffer overflow vulnerability in the convert_fname() function within src/url.c that allows remote attackers to trigger memory corruption through a server-supplied filename requiring character set conversion. When the output buffer is too small during iconv E2BIG reallocation, the reallocation logic miscalculates the remaining space, leading to a heap buffer overflow that can be exploited via a maliciously crafted server response.
GNU Wget 1.25.0 Integer Overflow via Content-Range Header Parsing
GNU Wget through 1.25.0, fixed in commit 43d3ba9, contains an integer overflow vulnerability in the parse_content_range() function within src/http.c that allows server-controlled values to cause signed integer arithmetic to overflow. Attackers can supply malicious Content-Range header values to trigger undefined behavior and download desynchronization in the affected client.
GNU Wget 1.25.0 Heap Buffer Underread via Metalink URL Parsing
GNU Wget through 1.25.0, fixed in commit 37a40fc, contains a heap buffer underread vulnerability in the clean_metalink_string() function within src/metalink.c that allows a malicious server to trigger memory corruption by serving a Metalink document containing a whitespace-only URL. Attackers can cause the function to decrement a pointer past the start of the buffer when processing an all-whitespace Metalink URL, potentially leading to abnormal program behavior.
GNU Wget is vulnerable to an SSRF attack when accessing partially-user-controlled shorthand URLs
Applications that use Wget to access a remote resource using shorthand URLs and pass arbitrary user credentials in the URL are vulnerable. In these cases attackers can enter crafted credentials which will cause Wget to access an arbitrary host.
url.c in GNU Wget through 1.24.5 mishandles semicolons in the userinfo subcomponent of a URI, and thus there may be insecure behavior in which data that was supposed to be in the userinfo subcomponent is misinterpreted to be part of the host subcomponent.
Buffer overflow in GNU Wget 1.20.1 and earlier allows remote attackers to cause a denial-of-service (DoS) or may execute an arbitrary code via unspecified vectors.
set_file_metadata in xattr.c in GNU Wget before 1.20.1 stores a file's origin URL in the user.xdg.origin.url metadata attribute of the extended attributes of the downloaded file, which allows local users to obtain sensitive information (e.g., credentials contained in the URL) by reading this attribute, as demonstrated by getfattr. This also applies to Referer information in the user.xdg.referrer.url metadata attribute. According to 2016-07-22 in the Wget ChangeLog, user.xdg.origin.url was partially based on the behavior of fwrite_xattr in tool_xattr.c in curl.
The retr.c:fd_read_body() function is called when processing OK responses. When the response is sent chunked in wget before 1.19.2, the chunk parser uses strtol() to read each chunk's length, but doesn't check that the chunk length is a non-negative number. The code then tries to read the chunk in pieces of 8192 bytes by using the MIN() macro, but ends up passing the negative chunk length to retr.c:fd_read(). As fd_read() takes an int argument, the high 32 bits of the chunk length are discarded, leaving fd_read() with a completely attacker controlled length argument. The attacker can corrupt malloc metadata after the allocated buffer.
GNU Wget: stack overflow in HTTP protocol handling
The http.c:skip_short_body() function is called in some circumstances, such as when processing redirects. When the response is sent chunked in wget before 1.19.2, the chunk parser uses strtol() to read each chunk's length, but doesn't check that the chunk length is a non-negative number. The code then tries to skip the chunk in pieces of 512 bytes by using the MIN() macro, but ends up passing the negative chunk length to connect.c:fd_read(). As fd_read() takes an int argument, the high 32 bits of the chunk length are discarded, leaving fd_read() with a completely attacker controlled length argument.
CRLF injection vulnerability in the url_parse function in url.c in Wget through 1.19.1 allows remote attackers to inject arbitrary HTTP headers via CRLF sequences in the host subcomponent of a URL.
Race condition in wget 1.17 and earlier, when used in recursive or mirroring mode to download a single file, might allow remote servers to bypass intended access list restrictions by keeping an HTTP connection open.
Non évaluéeEPSS 39,88%Code d’exploitation publicCorrectif disponible
CVE-2014-4877
Absolute path traversal vulnerability in GNU Wget before 1.16, when recursion is enabled, allows remote FTP servers to write to arbitrary files, and consequently execute arbitrary code, via a LIST response that references the same filename within two entries, one of which indicates that the filename is for a symlink.
GNU Wget 1.12 and earlier uses a server-provided filename instead of the original URL to determine the destination filename of a download, which allows remote servers to create or overwrite arbitrary files via a 3xx redirect to a URL with a .wgetrc filename followed by a 3xx redirect to a URL with a crafted filename, and possibly execute arbitrary code as a consequence of writing to a dotfile in a home directory.
GNU Wget before 1.12 does not properly handle a '\0' character in a domain name in the Common Name field of an X.509 certificate, which allows man-in-the-middle remote attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408.