Bug 479932 (CVE-2009-0028)

Summary: CVE-2009-0028 Linux kernel minor signal handling vulnerability
Product: [Other] Security Response Reporter: Eugene Teo (Security Response) <eteo>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED ERRATA QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: bhu, dhoward, ghelleks, lgoncalv, mjc, nobody, onestero, rkhan, security-response-team, vgoyal, williams
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2021-10-19 09:06:38 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 479957, 479958, 479959, 479960, 479961, 479962, 479963, 479964    
Bug Blocks:    
Attachments:
Description Flags
Demo program #2
none
clone ->exit_signal with CLONE_PARENT
none
Upstream patch none

Description Eugene Teo (Security Response) 2009-01-14 06:44:37 UTC 
From Chris Evans:

It's a relatively minor signal issue where a child can send its parent process an arbitrary signal, even if the parent has a totally separate real and effective user id. This could be a nuisance in the case where long-running root daemons spawn direct child processes owned by untrusted users [*]. There may even be worse consequences if privileged processes have weak signal handling code for signals not normally triggerable by untrusted users.
Comment 4 Eugene Teo (Security Response) 2009-01-14 08:57:29 UTC 
man clone:
The low byte of flags contains the number  of  the  termination  signal sent to the parent when the child dies.  If this signal is specified as anything other than SIGCHLD, then the parent process must  specify  the __WALL or __WCLONE options when waiting for the child with wait(2).  If no signal is specified, then the parent process is  not  signaled  when the child terminates.
Comment 30 Eugene Teo (Security Response) 2009-02-25 07:38:16 UTC 
It's public now:
http://scarybeastsecurity.blogspot.com/2009/02/linux-kernel-minor-signal-vulnerability.html
Comment 31 Eugene Teo (Security Response) 2009-02-25 07:43:33 UTC 
http://scary.beasts.org/security/CESA-2009-002.html
Comment 37 Eugene Teo (Security Response) 2009-03-11 00:31:10 UTC 
Created attachment 334735 [details]
Upstream patch

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=2d5516cbb9daf7d0e342a2e3b0fc6f8c39a81205
Comment 38 errata-xmlrpc 2009-04-01 08:30:52 UTC 
This issue has been addressed in following products:

  Red Hat Enterprise Linux 5

Via RHSA-2009:0326 https://rhn.redhat.com/errata/RHSA-2009-0326.html
Comment 41 errata-xmlrpc 2009-04-29 09:28:36 UTC 
This issue has been addressed in following products:

  MRG for RHEL-5

Via RHSA-2009:0451 https://rhn.redhat.com/errata/RHSA-2009-0451.html
Comment 42 errata-xmlrpc 2009-04-30 21:25:00 UTC 
This issue has been addressed in following products:

  Red Hat Enterprise Linux 4

Via RHSA-2009:0459 https://rhn.redhat.com/errata/RHSA-2009-0459.html