Candidate: CVE-2004-2136
References: 
 http://marc.theaimsgroup.com/?l=linux-kernel&m=107719798631935&w=2
 http://mareichelt.de/pub/notmine/diskenc.pdf
 http://www.securiteam.com/exploits/5UP0P1PFPM.html
Description: 
 dm-crypt on Linux kernel 2.6.x, when used on certain file systems with a
 block size 1024 or greater, has certain "IV computation" weaknesses that
 allow watermarked files to be detected without decryption.
Notes: 
 jmm> IIRC there was some serious flaming about the different disk encryption systems,
 jmm> I'm not sure whether this has been addressed or how real it is
 jmm> 2.4 doesn't have dm-crypt, though
Bugs: 
upstream: 
linux-2.6:
2.6.8-sarge-security: ignored (2.6.8-16sarge5)
2.4.27-sarge-security: N/A
2.6.18-etch-security: ignored