# CVE-2009-2695: The Linux kernel before 2.6.31-rc7 does not properly prevent mmap operations that target page zero and other low memory addresses, which all

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2009-08-28 · Updated: 2024-08-07

## Affected

- n/a: version range not reported

## Description

The Linux kernel before 2.6.31-rc7 does not properly prevent mmap operations that target page zero and other low memory addresses, which allows local users to gain privileges by exploiting NULL pointer dereference vulnerabilities, related to (1) the default configuration of the allow_unconfined_mmap_low boolean in SELinux on Red Hat Enterprise Linux (RHEL) 5, (2) an error that causes allow_unconfined_mmap_low to be ignored in the unconfined_t domain, (3) lack of a requirement for the CAP_SYS_RAWIO capability for these mmap operations, and (4) interaction between the mmap_min_addr protection mechanism and certain application programs.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
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  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2009-2695

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- http://www.kernel.org/pub/linux/kernel/v2.6/testing/ChangeLog-2.6.31-rc7
- http://www.redhat.com/support/errata/RHSA-2009-1672.html
- http://git.kernel.org/?p=linux/kernel/git/jmorris/security-testing-2.6.git%3Ba=commit%3Bh=84336d1a77ccd2c06a730ddd38e695c2324a7386
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=1d9959734a1949ea4f2427bd2d8b21ede6b2441c
- http://www.securityfocus.com/bid/36051
- https://rhn.redhat.com/errata/RHSA-2009-1540.html
- https://bugzilla.redhat.com/show_bug.cgi?id=517830
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=ab5a91a8364c3d6fc617abc47cc81d162c01d90a
- http://www.ubuntu.com/usn/USN-852-1
- http://secunia.com/advisories/38794
- http://lists.vmware.com/pipermail/security-announce/2010/000082.html
- http://patchwork.kernel.org/patch/36540/
- http://git.kernel.org/?p=linux/kernel/git/jmorris/security-testing-2.6.git%3Ba=commit%3Bh=47d439e9fb8a81a90022cfa785bf1c36c4e2aff6
- http://patchwork.kernel.org/patch/36539/
- http://kbase.redhat.com/faq/docs/DOC-18042
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=788084aba2ab7348257597496befcbccabdc98a3
- http://eparis.livejournal.com/606.html
- http://twitter.com/spendergrsec/statuses/3303390960
- https://bugzilla.redhat.com/show_bug.cgi?id=511143
- https://www.redhat.com/archives/fedora-package-announce/2009-August/msg01256.html
- http://patchwork.kernel.org/patch/36649/
- https://rhn.redhat.com/errata/RHSA-2009-1548.html
- http://thread.gmane.org/gmane.linux.kernel.lsm/9075
- http://git.kernel.org/?p=linux/kernel/git/jmorris/security-testing-2.6.git%3Ba=commit%3Bh=a2551df7ec568d87793d2eea4ca744e86318f205
- http://secunia.com/advisories/38834

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