I am trying to use curl to connect to a site using HTTPS. But curl is failing to verify the SSL cert. $ curl --verbose --capath ./certs/ --head https://example.com/ * About to connect() to example.com port 443 (#0) * Trying 1.1.1.1... connected * Connected to example.com (1.1.1.1) port 443 (#0) * successfully set certificate verify locations: * CAfile: none CApath: ./certs/ * SSLv3, TLS handshake, Client hello (1): * SSLv3, TLS handshake, Server hello (2): * SSLv3, TLS handshake, CERT (11): * SSLv3, TLS alert, Server hello (2): * SSL certificate problem, verify that the CA cert is OK. Details: error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed * Closing connection #0 curl: (60) SSL certificate problem, verify that the CA cert is OK. Details: error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed More details here: http://curl.haxx.se/docs/sslcerts.html curl performs SSL certificate verification by default, using a "bundle" of Certificate Authority (CA) public keys (CA certs). If the default bundle file isn't adequate, you can specify an alternate file using the --cacert option. If this HTTPS server uses a certificate signed by a CA represented in the bundle, the certificate verification probably failed due to a problem with the certificate (it might be expired, or the name might not match the domain name in the URL). If you'd like to turn off curl's verification of the certificate, use the -k (or --insecure) option. I know about the -k option. But I do actually want to verify the cert. The certs directory has been properly hashed with c_rehash . and it contains: A Verisign intermediate cert Two self-signed certs The above site should be verified with the Verisign intermediate cert. When I use the --cacert option instead (and point directly to the Verisign cert) curl is able to verify the SSL cert. $ curl --verbose --cacert ./certs/verisign-intermediate-ca.crt --head https://example.com/ * About to connect() to example.com port 443 (#0) * Trying 1.1.1.1... connected * Connected to example.com (1.1.1.1) port 443 (#0) * successfully set certificate verify locations: * CAfile: ./certs/verisign-intermediate-ca.crt CApath: /etc/ssl/certs * SSLv3, TLS handshake, Client hello (1): * SSLv3, TLS handshake, Server hello (2): * SSLv3, TLS handshake, CERT (11): * SSLv3, TLS handshake, Server finished (14): * SSLv3, TLS handshake, Client key exchange (16): * SSLv3, TLS change cipher, Client hello (1): * SSLv3, TLS handshake, Finished (20): * SSLv3, TLS change cipher, Client hello (1): * SSLv3, TLS handshake, Finished (20): * SSL connection using RC4-SHA * Server certificate: * subject: C=US; ST=State; L=City; O=Company; OU=ou1; CN=example.com * start date: 2011-04-17 00:00:00 GMT * expire date: 2012-04-15 23:59:59 GMT * common name: example.com (matched) * issuer: C=US; O=VeriSign, Inc.; OU=VeriSign Trust Network; OU=Terms of use at https://www.verisign.com/rpa (c)10; CN=VeriSign Class 3 Secure Server CA - G3 * SSL certificate verify ok. > HEAD / HTTP/1.1 > User-Agent: curl/7.19.7 (x86_64-pc-linux-gnu) libcurl/7.19.7 OpenSSL/0.9.8k zlib/1.2.3.3 libidn/1.15 > Host: example.com > Accept: */* > < HTTP/1.1 404 Not Found HTTP/1.1 404 Not Found < Cache-Control: must-revalidate,no-cache,no-store Cache-Control: must-revalidate,no-cache,no-store < Content-Type: text/html;charset=ISO-8859-1 Content-Type: text/html;charset=ISO-8859-1 < Content-Length: 1267 Content-Length: 1267 < Server: Jetty(7.2.2.v20101205) Server: Jetty(7.2.2.v20101205) < * Connection #0 to host example.com left intact * Closing connection #0 * SSLv3, TLS alert, Client hello (1): In addition, if I try hitting one of the sites using a self signed cert and the --capath option, it also works. (Let me know if I should post an example of that.) This implies that curl is finding the cert directory, and it is properly hash. Finally, I am able to verify the SSL cert with openssl, using its -CApath option. $ openssl s_client -CApath ./certs/ -connect example.com:443 CONNECTED(00000003) depth=3 /C=US/O=VeriSign, Inc./OU=Class 3 Public Primary Certification Authority verify return:1 depth=2 /C=US/O=VeriSign, Inc./OU=VeriSign Trust Network/OU=(c) 2006 VeriSign, Inc. - For authorized use only/CN=VeriSign Class 3 Public Primary Certification Authority - G5 verify return:1 depth=1 /C=US/O=VeriSign, Inc./OU=VeriSign Trust Network/OU=Terms of use at https://www.verisign.com/rpa (c)10/CN=VeriSign Class 3 Secure Server CA - G3 verify return:1 depth=0 /C=US/ST=State/L=City/O=Company/OU=ou1/CN=example.com verify return:1 --- Certificate chain 0 s:/C=US/ST=State/L=City/O=Company/OU=ou1/CN=example.com i:/C=US/O=VeriSign, Inc./OU=VeriSign Trust Network/OU=Terms of use at https://www.verisign.com/rpa (c)10/CN=VeriSign Class 3 Secure Server CA - G3 --- Server certificate -----BEGIN CERTIFICATE----- <cert removed> -----END CERTIFICATE----- subject=/C=US/ST=State/L=City/O=Company/OU=ou1/CN=example.com issuer=/C=US/O=VeriSign, Inc./OU=VeriSign Trust Network/OU=Terms of use at https://www.verisign.com/rpa (c)10/CN=VeriSign Class 3 Secure Server CA - G3 --- No client certificate CA names sent --- SSL handshake has read 1563 bytes and written 435 bytes --- New, TLSv1/SSLv3, Cipher is RC4-SHA Server public key is 2048 bit Secure Renegotiation IS NOT supported Compression: NONE Expansion: NONE SSL-Session: Protocol : TLSv1 Cipher : RC4-SHA Session-ID: D65C4C6D52E183BF1E7543DA6D6A74EDD7D6E98EB7BD4D48450885188B127717 Session-ID-ctx: Master-Key: 253D4A3477FDED5FD1353D16C1F65CFCBFD78276B6DA1A078F19A51E9F79F7DAB4C7C98E5B8F308FC89C777519C887E2 Key-Arg : None Start Time: 1303258052 Timeout : 300 (sec) Verify return code: 0 (ok) --- QUIT DONE How can I get curl to verify this cert using the --capath option?