CVE-2009-1895
What it is
The personality subsystem in the Linux kernel before 2.6.31-rc3 has a PER_CLEAR_ON_SETID setting that does not clear the ADDR_COMPAT_LAYOUT and MMAP_PAGE_ZERO flags when executing a setuid or setgid program, which makes it easier for local users to leverage the details of memory usage to (1) conduct NULL pointer dereference attacks, (2) bypass the mmap_min_addr protection mechanism, or (3) defeat address space layout randomization (ASLR).
At a glance
- Exploitability
- Can be exploited locally on the machine without logging in. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.4% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.4% in the next 30 days (EPSS).
- Severity: 7.2 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.4% · EPSS, next 30 days
- Weakness
- CWE-16
- Record status
- Modified
Affected
- Linux Kernel ≤ 2.6.31
- Linux Kernel 2.6.31
- Debian Linux 4.0
- Debian Linux 5.0
- Canonical Ubuntu Linux 6.06
- Canonical Ubuntu Linux 8.04
- Canonical Ubuntu Linux 8.10
- Canonical Ubuntu Linux 9.04
Attack profile CVSS 2.0 · 7.2
- Attack vector
- Local
- Complexity
- Low
- Authentication
- None
- Confidentiality
- Complete
- Integrity
- Complete
- Availability
- Complete
Raw vector
AV:L/AC:L/Au:N/C:C/I:C/A:C
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2009-1895.md and follow it. Check whether this project is affected by CVE-2009-1895. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- http://blog.cr0.org/2009/06/bypassing-linux-null-pointer.html
- http://patchwork.kernel.org/patch/32598/
- http://www.kernel.org/pub/linux/kernel/v2.6/testing/ChangeLog-2.6.31-rc3
- http://www.vupen.com/english/advisories/2009/1866
- http://blog.cr0.org/2009/06/bypassing-linux-null-pointer.html
- http://patchwork.kernel.org/patch/32598/
- http://www.kernel.org/pub/linux/kernel/v2.6/testing/ChangeLog-2.6.31-rc3
- http://www.vupen.com/english/advisories/2009/1866
References
- http://blog.cr0.org/2009/06/bypassing-linux-null-pointer.html
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=f9fabcb58a6d26d6efde842d1703ac7cfa9427b6
- http://patchwork.kernel.org/patch/32598/
- http://secunia.com/advisories/35801
- http://secunia.com/advisories/36045
- http://secunia.com/advisories/36051
- http://secunia.com/advisories/36054
- http://secunia.com/advisories/36116
- http://secunia.com/advisories/36131
- http://secunia.com/advisories/36759
- http://secunia.com/advisories/37471
- http://wiki.rpath.com/Advisories:rPSA-2009-0111
- http://www.debian.org/security/2009/dsa-1844
- http://www.debian.org/security/2009/dsa-1845
- http://www.kernel.org/pub/linux/kernel/v2.6/testing/ChangeLog-2.6.31-rc3
- http://www.mandriva.com/security/advisories?name=MDVSA-2011:051
- http://www.osvdb.org/55807
- http://www.redhat.com/support/errata/RHSA-2009-1193.html
- http://www.redhat.com/support/errata/RHSA-2009-1438.html
- http://www.securityfocus.com/archive/1/505254/100/0/threaded
- http://www.securityfocus.com/archive/1/507985/100/0/threaded
- http://www.securityfocus.com/archive/1/512019/100/0/threaded
- http://www.securityfocus.com/bid/35647
- http://www.ubuntu.com/usn/usn-807-1
- http://www.vmware.com/security/advisories/VMSA-2009-0016.html