Vulnerability Description
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).
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux Kernel | <= 2.6.31 |
| Debian | Debian Linux | 4.0 |
| Canonical | Ubuntu Linux | 6.06 |
Related Weaknesses (CWE)
References
- http://blog.cr0.org/2009/06/bypassing-linux-null-pointer.htmlPatchThird Party Advisory
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=
- http://patchwork.kernel.org/patch/32598/PatchVendor Advisory
- http://secunia.com/advisories/35801Third Party Advisory
- http://secunia.com/advisories/36045Third Party Advisory
- http://secunia.com/advisories/36051Third Party Advisory
- http://secunia.com/advisories/36054Third Party Advisory
- http://secunia.com/advisories/36116Third Party Advisory
- http://secunia.com/advisories/36131Third Party Advisory
- http://secunia.com/advisories/36759Third Party Advisory
- http://secunia.com/advisories/37471Third Party Advisory
- http://wiki.rpath.com/Advisories:rPSA-2009-0111Third Party Advisory
- http://www.debian.org/security/2009/dsa-1844Third Party Advisory
- http://www.debian.org/security/2009/dsa-1845Third Party Advisory
- http://www.kernel.org/pub/linux/kernel/v2.6/testing/ChangeLog-2.6.31-rc3Vendor Advisory
FAQ
What is CVE-2009-1895?
CVE-2009-1895 is a vulnerability with a CVSS score of 7.2 (HIGH). 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 p...
How severe is CVE-2009-1895?
CVE-2009-1895 has been rated HIGH with a CVSS base score of 7.2/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2009-1895?
Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel, Debian Debian Linux, Canonical Ubuntu Linux.