=========================================================== == Subject: Remote DoS against smbd on authenticated == connections == == CVE ID#: CVE-2009-2906 == == Versions: All known versions of samba == == Summary: Specially crafted SMB requests on == authenticated SMB connections can send smbd == into a 100% CPU loop, causing a DoS on the == Samba server =========================================================== =========== Description =========== Smbd is susceptible to a remote DoS attack by an authenticated remote client. If the client sends a reply to an oplock break notification that Samba does not expect it can cause smbd to spin the CPU repeatedly trying to process the unexpected packet and being unable to finish the processing. This is unlikely to happen with normal client activity (although not impossible). ================== Patch Availability ================== A Patch addressing this issue has been posted to: http://www.samba.org/samba/security/ Additionally, Samba 3.0.37, 3.2.15, 3.3.8 and 3.4.2 have been issued as security releases to correct the defect. Samba administrators are advised to upgrade to these releases or apply the patch as soon as possible. ========== Workaround ========== None available ======= Credits ======= Originally reported by Tim Prouty, Isilon and Samba Team Patches provided by Jeremy Allison, Samba Team ========================================================== == Our Code, Our Bugs, Our Responsibility. == The Samba Team ==========================================================