oss-sec mailing list archives
CVE-2010-2524 kernel: dns_resolver upcall security issue
From: Eugene Teo <eugeneteo () kernel sg>
Date: Mon, 02 Aug 2010 11:47:54 +0800
CIFS has the ability to chase MS-DFS referrals. In order to do this it has to be able to resolve hostnames into IP addresses. For this, it uses the keys API to upcall to the cifs.upcall userspace helper. It then resolves the name and hands the address back to the kernel.
The dns_resolver upcall currently used by CIFS is susceptible to cachestuffing. It's possible for a malicious user to stuff the keyring with the results of a lookup, and then trick the server into mounting a server of his choosing.
I have assigned this with CVE-2010-2524. To be susceptible to this, you need CONFIG_CIFS_DFS_UPCALL enabled. Interesting bug.
https://bugzilla.redhat.com/CVE-2010-2524 Upstream commit: http://git.kernel.org/linus/4c0c03ca54f72fdd5912516ad0a23ec5cf01bda7 Thanks, Eugene -- main(i) { putchar(182623909 >> (i-1) * 5&31|!!(i<7)<<6) && main(++i); }
Current thread:
- CVE-2010-2524 kernel: dns_resolver upcall security issue Eugene Teo (Aug 01)
- Re: CVE-2010-2524 kernel: dns_resolver upcall security issue akuster (Aug 02)
- Re: CVE-2010-2524 kernel: dns_resolver upcall security issue Eugene Teo (Aug 02)
- Re: CVE-2010-2524 kernel: dns_resolver upcall security issue akuster (Aug 02)