Hash-Kollision in rdiff-backup
ID: | FEDORA-2015-3497 |
Distribution: | Fedora |
Plattformen: | Fedora 21 |
Datum: | Fr, 20. März 2015, 00:04 |
Referenzen: | http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2014-8242 |
Applikationen: | rdiff-backup |
Originalnachricht |
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Name : rdiff-backup Product : Fedora 21 Version : 1.2.8 Release : 14.fc21 URL : http://www.nongnu.org/rdiff-backup/ Summary : Convenient and transparent local/remote incremental mirror/backup Description : rdiff-backup is a script, written in Python, that backs up one directory to another and is intended to be run periodically (nightly from cron for instance). The target directory ends up a copy of the source directory, but extra reverse diffs are stored in the target directory, so you can still recover files lost some time ago. The idea is to combine the best features of a mirror and an incremental backup. rdiff-backup can also operate in a bandwidth efficient manner over a pipe, like rsync. Thus you can use rdiff-backup and ssh to securely back a hard drive up to a remote location, and only the differences from the previous backup will be transmitted. -------------------------------------------------------------------------------- Update Information: Changes in librsync 1.0.0 (2015-01-23) ====================================== * SECURITY: CVE-2014-8242: librsync previously used a truncated MD4 "strong" check sum to match blocks. However, MD4 is not cryptographically strong. It's possible that an attacker who can control the contents of one part of a file could use it to control other regions of the file, if it's transferred using librsync/rdiff. For example this might occur in a database, mailbox, or VM image containing some attacker-controlled data. To mitigate this issue, signatures will by default be computed with a 256-bit BLAKE2 hash. Old versions of librsync will complain about a bad magic number when given these signature files. Backward compatibility can be obtained using the new `rdiff sig --hash=md4` option or through specifying the "signature magic" in the API, but this should not be used when either the old or new file contain untrusted data. Deltas generated from those signatures will also use BLAKE2 during generation, but produce output that can be read by old versions. See https://github.com/librsync/librsync/issues/5. Thanks to Michael Samuel |