721288 - CERT_PKIXVerifyCert chains one self-signed certificate of a root CA to another self-signed certificate of the same root CA

Status: NEW

(NSS :: Libraries, defect, P2)

Description

[Wan-Teh Chang]

This problem was first reported in Chromium bug 108514:
http://code.google.com/p/chromium/issues/detail?id=108514

If NSS has two self-signed certificates of the same root CA, CERT_PKIXVerifyCert
may chain one of them to the other.  I suspect this is because libpkix's certificate
chain building code does not stop when it has reached a self-signed root certificate.

The classic NSS certificate verification code checks cert->isRoot when building
certificate chains.  For example, see
http://bonsai.mozilla.org/cvsblame.cgi?file=mozilla/security/nss/lib/pki/certificate.c&rev=1.68&mark=510-516#508
http://bonsai.mozilla.org/cvsblame.cgi?file=mozilla/security/nss/lib/certhigh/certvfy.c&rev=1.75&mark=1841-1846#1834
http://bonsai.mozilla.org/cvsblame.cgi?file=mozilla/security/nss/lib/certhigh/certvfy.c&rev=1.75&mark=667-674#667

https://images.etrade.wallst.com/ is a website that exhibits this problem.
In the SSL handshake the server sends an old self-signed certificate of the root
CA.  CERT_PKIXVerifyCert chains that root certificate to the root certificate in
the built-in root certificates module.  I will attach the three certificates sent
by the server next.

Comment 1

[Wan-Teh Chang]

Attachment: cert.001: the server certificate for https://images.etrade.wallst.com/

Comment 2

[Wan-Teh Chang]

Attachment: cert.002: the intermediate CA certificate for https://images.etrade.wallst.com/

Comment 3

[Wan-Teh Chang]

Attachment: cert.003: the old root certificate for https://images.etrade.wallst.com/

Comment 4

[Brian Smith (:briansmith, :bsmith, use NEEDINFO?)]

This sounds very similar to bug 489714. See especially bug 489714 comment 3 and below.