curl before version 7.52.0 is vulnerable to a buffer overflow when doing a large floating point output in libcurl's implementation of the printf() functions. If there are any application that accepts a format string from the outside without necessary input filtering, it could allow remote attacks.

A buffer over-read exists in curl 7.20.0 to and including curl 7.58.0 in the RTSP+RTP handling code that allows an attacker to cause a denial of service or information leakage

A NULL pointer dereference exists in curl 7.21.0 to and including curl 7.58.0 in the LDAP code that allows an attacker to cause a denial of service

A buffer overflow exists in curl 7.12.3 to and including curl 7.58.0 in the FTP URL handling that allows an attacker to cause a denial of service or worse.

libcurl 7.1 through 7.57.0 might accidentally leak authentication data to third parties. When asked to send custom headers in its HTTP requests, libcurl will send that set of headers first to the host in the initial URL but also, if asked to follow redirects and a 30X HTTP response code is returned, to the host mentioned in URL in the `Location:` response header value. Sending the same set of headers to subsequent hosts is in particular a problem for applications that pass on custom `Authorization:` headers, as this header often contains privacy sensitive information or data that could allow others to impersonate the libcurl-using client's request.

The FTP wildcard function in curl and libcurl before 7.57.0 allows remote attackers to cause a denial of service (out-of-bounds read and application crash) or possibly have unspecified other impact via a string that ends with an '[' character.

In curl before 7.54.1 on Windows and DOS, libcurl's default protocol function, which is the logic that allows an application to set which protocol libcurl should attempt to use when given a URL without a scheme part, had a flaw that could lead to it overwriting a heap based memory buffer with seven bytes. If the default protocol is specified to be FILE or a file: URL lacks two slashes, the given "URL" starts with a drive letter, and libcurl is built for Windows or DOS, then libcurl would copy the path 7 bytes off, so that the end of the given path would write beyond the malloc buffer (7 bytes being the length in bytes of the ascii string "file://").

Multiple untrusted search path vulnerabilities in cURL and libcurl before 7.49.1, when built with SSPI or telnet is enabled, allow local users to execute arbitrary code and conduct DLL hijacking attacks via a Trojan horse (1) security.dll, (2) secur32.dll, or (3) ws2_32.dll in the application or current working directory.

The (1) mbed_connect_step1 function in lib/vtls/mbedtls.c and (2) polarssl_connect_step1 function in lib/vtls/polarssl.c in cURL and libcurl before 7.49.0, when using SSLv3 or making a TLS connection to a URL that uses a numerical IP address, allow remote attackers to spoof servers via an arbitrary valid certificate.

The ConnectionExists function in lib/url.c in libcurl before 7.47.0 does not properly re-use NTLM-authenticated proxy connections, which might allow remote attackers to authenticate as other users via a request, a similar issue to CVE-2014-0015.

cURL before 7.47.0 on Windows allows attackers to write to arbitrary files in the current working directory on a different drive via a colon in a remote file name.

The default configuration for cURL and libcurl before 7.42.1 sends custom HTTP headers to both the proxy and destination server, which might allow remote proxy servers to obtain sensitive information by reading the header contents.

cURL and libcurl 7.10.6 through 7.41.0 do not properly re-use authenticated Negotiate connections, which allows remote attackers to connect as other users via a request.

cURL and libcurl 7.10.6 through 7.41.0 does not properly re-use NTLM connections, which allows remote attackers to connect as other users via an unauthenticated request, a similar issue to CVE-2014-0015.

cURL and libcurl before 7.38.0 allow remote attackers to bypass the Same Origin Policy and set cookies for arbitrary sites by setting a cookie for a top-level domain.

cURL and libcurl before 7.38.0 does not properly handle IP addresses in cookie domain names, which allows remote attackers to set cookies for or send arbitrary cookies to certain sites, as demonstrated by a site at 192.168.0.1 setting cookies for a site at 127.168.0.1.

curl and libcurl 7.27.0 through 7.35.0, when running on Windows and using the SChannel/Winssl TLS backend, does not verify that the server hostname matches a domain name in the subject's Common Name (CN) or subjectAltName field of the X.509 certificate when accessing a URL that uses a numerical IP address, which allows man-in-the-middle attackers to spoof servers via an arbitrary valid certificate.

cURL and libcurl 7.1 before 7.36.0, when using the OpenSSL, axtls, qsossl or gskit libraries for TLS, recognize a wildcard IP address in the subject's Common Name (CN) field of an X.509 certificate, which might allow man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority.

The default configuration in cURL and libcurl 7.10.6 before 7.36.0 re-uses (1) SCP, (2) SFTP, (3) POP3, (4) POP3S, (5) IMAP, (6) IMAPS, (7) SMTP, (8) SMTPS, (9) LDAP, and (10) LDAPS connections, which might allow context-dependent attackers to connect as other users via a request, a similar issue to CVE-2014-0015.

cURL and libcurl 7.10.6 through 7.34.0, when more than one authentication method is enabled, re-uses NTLM connections, which might allow context-dependent attackers to authenticate as other users via a request.