curl might erroneously pass on credentials for a first proxy to a second proxy.
This can happen when the following conditions are true:
1. curl is setup to use specific different proxies for different URL schemes 2. the first proxy needs credentials 3. the second proxy uses no credentials 4. while using the first proxy (using say http://), curl is asked to follow a redirect to a URL using another scheme (say https://), accessed using a second, different, proxy
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 7.1 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.
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.
Curl versions 7.14.1 through 7.61.1 are vulnerable to a heap-based buffer over-read in the toolmsgs.c:voutf() function.
This display function formats the output to wrap at 80 columns. The wrap logic is however flawed, so if a single word in the message is itself longer than 80 bytes the buffer arithmetic calculates the remainder wrong and will end up reading behind the end of the buffer. This could lead to information disclosure or crash.