# What is CVE-2009-2692?

> CVE-2009-2692 is a high-severity flaw (CVSS 7.8) in Linux kernel, published on 14 August 2009. It is not on the list of flaws known to be exploited today. The latest forecast puts its chance of use in the next 30 days at 15%. If you run an affected version, plan in the vendor’s fix.

Canonical page: https://www.precursorintelligence.com/what-is/cve-2009-2692

## At a glance

- **Verdict:** Fix this soon. Not confirmed as exploited yet, but serious or likely enough that it should not wait for a quiet month.
- **Precursor Intelligence risk score:** 47 out of 100 (Medium); action: Plan remediation. Kept up to date as the evidence changes.
- **Severity:** High (CVSS 7.8 out of 10)
- **Known to be exploited:** No, not on the list of flaws known to be exploited today
- **Chance of use in the next 30 days:** 15% (latest exploit-likelihood forecast)
- **Published:** 14 August 2009
- **Record last updated:** 16 June 2026
- **Main product:** Linux kernel
- **Affected products:** 8

## What is CVE-2009-2692? In plain terms

An attacker has to be already on the device with an ordinary user account, and nobody has to click anything. If it works, the attacker can read data, change data and take it offline.

### The official description

The Linux kernel 2.6.0 through 2.6.30.4, and 2.4.4 through 2.4.37.4, does not initialize all function pointers for socket operations in proto_ops structures, which allows local users to trigger a NULL pointer dereference and gain privileges by using mmap to map page zero, placing arbitrary code on this page, and then invoking an unavailable operation, as demonstrated by the sendpage operation (sock_sendpage function) on a PF_PPPOX socket.

### What kind of flaw is it?

- CWE-908: Use of Uninitialized Resource

### How an attack on it works

- Where an attacker can be: Already on the device
- How hard it is to pull off: Easy: no special conditions
- Login needed first: An ordinary user account
- Does someone have to click: No, nobody has to do anything
- What an attacker gets: Can read data, change data and take it offline

Severity vector: `CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`

## Is CVE-2009-2692 being exploited? Not that we know of

It is not on the list of flaws known to be exploited today. The latest forecast puts the chance of it being used in the next 30 days at 15%. That can change at any time, which is why we keep watching.

Exploit likelihood over the last 7 days: 15%, 15%, 15%, 15%, 15%, 15%, 15%.

### Timeline

- 14 August 2009: Published
- 16 June 2026: Record last updated

### How Precursor Intelligence ranks it

CVE-2009-2692 scores **47 out of 100 (Medium)**, with the action "Plan remediation".

Every published flaw gets a risk score from 0 to 100, kept up to date as the evidence changes. Four things go into the score, from the one that counts most to the ones that count less:

- Evidence it is being exploited: biggest factor
- How severe it is: strong factor
- How widely exposed it is: smaller factor
- Threat activity around it: smaller factor

85 and above is Critical. Anything confirmed as exploited is always marked for an emergency patch, whatever its score. When this flaw matches software you track, it lands in your list with its score and the reasons behind it.

## Who is affected by CVE-2009-2692?

The published record lists 8 products. Versions are as published: "2.4.4 to before 2.4.37.5" means from 2.4.4 up to, but not including, 2.4.37.5.

- [Linux kernel](https://www.precursorintelligence.com/product/linux/linux_kernel) by [Linux](https://www.precursorintelligence.com/vendors/linux) (Operating system): 2.4.4 to before 2.4.37.5, 2.6.0 to before 2.6.30.5
- [Enterprise Linux Desktop](https://www.precursorintelligence.com/product/redhat/enterprise_linux_desktop) by [Red Hat](https://www.precursorintelligence.com/vendors/redhat) (Operating system): 4.0, 5.0
- [Enterprise Linux Eus](https://www.precursorintelligence.com/product/redhat/enterprise_linux_eus) by [Red Hat](https://www.precursorintelligence.com/vendors/redhat) (Operating system): 4.8, 5.3
- [Enterprise Linux Server](https://www.precursorintelligence.com/product/redhat/enterprise_linux_server) by [Red Hat](https://www.precursorintelligence.com/vendors/redhat) (Operating system): 4.0, 5.0
- [Enterprise Linux Workstation](https://www.precursorintelligence.com/product/redhat/enterprise_linux_workstation) by [Red Hat](https://www.precursorintelligence.com/vendors/redhat) (Operating system): 4.0, 5.0
- [Debian Linux](https://www.precursorintelligence.com/product/debian/debian_linux) by [Debian](https://www.precursorintelligence.com/vendors/debian) (Operating system): 4.0
- [Enterprise Linux Server Aus](https://www.precursorintelligence.com/product/redhat/enterprise_linux_server_aus) by [Red Hat](https://www.precursorintelligence.com/vendors/redhat) (Operating system): 5.3
- [Linux Enterprise Real Time](https://www.precursorintelligence.com/product/suse/linux_enterprise_real_time) by [Suse](https://www.precursorintelligence.com/vendors/suse) (Operating system): 10

## How do I fix CVE-2009-2692?

1. **Check whether you run it.** Compare your versions with the affected products above. Not sure what you run? Precursor Intelligence can work it out from your public website, or you can pick it from a list.
2. **Apply the vendor’s fix.** Install the update named in the vendor’s advisory. We’ve put the advisories and patch notes first in the list.
3. **If you can’t patch today.** Follow any mitigation the vendor publishes, and limit who can reach the affected system from the internet until the update is in.
4. **Keep an eye on it.** Track the product and we tell you as soon as we spot this flaw on the list of exploited flaws, or a jump in its exploit likelihood.

### References

- [openwall.com](http://www.openwall.com/lists/oss-security/2009/08/14/1) (Mailing list, Patch)
- [vupen.com](http://www.vupen.com/english/advisories/2009/2272) (Broken link, Patch, Vendor advisory)
- [bugzilla.redhat.com](https://bugzilla.redhat.com/show_bug.cgi?id=516949) (Issue tracking, Patch)
- [secunia.com](http://secunia.com/advisories/36278) (Broken link, Vendor advisory)
- [secunia.com](http://secunia.com/advisories/36289) (Broken link, Vendor advisory)
- [secunia.com](http://secunia.com/advisories/36327) (Broken link, Vendor advisory)
- [secunia.com](http://secunia.com/advisories/36430) (Broken link, Vendor advisory)
- [secunia.com](http://secunia.com/advisories/37298) (Broken link, Vendor advisory)
- [secunia.com](http://secunia.com/advisories/37471) (Broken link, Vendor advisory)
- [kernel.org](http://www.kernel.org/pub/linux/kernel/v2.4/ChangeLog-2.4.37.5) (Broken link, Vendor advisory)
- [kernel.org](http://www.kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.30.5) (Broken link, Vendor advisory)
- [kernel.org](http://www.kernel.org/pub/linux/kernel/v2.6/testing/ChangeLog-2.6.31-rc6) (Broken link, Vendor advisory)
- [vupen.com](http://www.vupen.com/english/advisories/2009/3316) (Broken link, Vendor advisory)
- [archives.neohapsis.com](http://archives.neohapsis.com/archives/fulldisclosure/2009-08/0174.html) (Broken link, Exploit)
- [blog.cr0.org](http://blog.cr0.org/2009/08/linux-null-pointer-dereference-due-to.html) (Exploit, Issue tracking)
- [git.kernel.org](http://git.kernel.org/?p=linux/kernel/git/stable/linux-2.4.37.y.git%3Ba=commit%3Bh=c18d0fe535a73b219f960d1af3d0c264555a12e3) (Broken link)
- [git.kernel.org](http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=e694958388c50148389b0e9b9e9e8945cf0f1b98) (Broken link)
- [grsecurity.net](http://grsecurity.net/~spender/wunderbar_emporium.tgz) (Broken link)
- [lists.opensuse.org](http://lists.opensuse.org/opensuse-security-announce/2009-09/msg00001.html) (Mailing list)
- [rhn.redhat.com](http://rhn.redhat.com/errata/RHSA-2009-1222.html) (Third-party advisory)
- [rhn.redhat.com](http://rhn.redhat.com/errata/RHSA-2009-1223.html) (Third-party advisory)
- [support.avaya.com](http://support.avaya.com/css/P8/documents/100067254) (Third-party advisory)
- [wiki.rpath.com](http://wiki.rpath.com/wiki/Advisories:rPSA-2009-0121) (Broken link)
- [debian.org](http://www.debian.org/security/2009/dsa-1865) (Mailing list, Third-party advisory)
- [exploit-db.com](http://www.exploit-db.com/exploits/19933) (Exploit, Third-party advisory, Vulnerability database)
- [exploit-db.com](http://www.exploit-db.com/exploits/9477) (Third-party advisory, Vulnerability database)
- [mandriva.com](http://www.mandriva.com/security/advisories?name=MDVSA-2009:233) (Broken link)
- [redhat.com](http://www.redhat.com/support/errata/RHSA-2009-1233.html) (Broken link)
- [securityfocus.com](http://www.securityfocus.com/archive/1/505751/100/0/threaded) (Broken link, Third-party advisory, Vulnerability database)
- [securityfocus.com](http://www.securityfocus.com/archive/1/505912/100/0/threaded) (Broken link, Third-party advisory, Vulnerability database)
- [securityfocus.com](http://www.securityfocus.com/archive/1/507985/100/0/threaded) (Broken link, Third-party advisory, Vulnerability database)
- [securityfocus.com](http://www.securityfocus.com/archive/1/512019/100/0/threaded) (Broken link, Third-party advisory, Vulnerability database)
- [securityfocus.com](http://www.securityfocus.com/bid/36038) (Broken link, Exploit, Third-party advisory, Vulnerability database)
- [vmware.com](http://www.vmware.com/security/advisories/VMSA-2009-0016.html) (Third-party advisory)
- [zenthought.org](http://zenthought.org/content/file/android-root-2009-08-16-source) (Broken link)
- [issues.rpath.com](https://issues.rpath.com/browse/RPL-3103) (Broken link)
- [oval.cisecurity.org](https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11526) (Broken link)
- [oval.cisecurity.org](https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11591) (Broken link)
- [oval.cisecurity.org](https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A8657) (Broken link)

## Questions

### What is CVE-2009-2692?

CVE-2009-2692 is a high-severity flaw in Linux kernel, published on 14 August 2009. An attacker has to be already on the device with an ordinary user account, and nobody has to click anything. If it works, the attacker can read data, change data and take it offline.

### How serious is CVE-2009-2692?

It scores 7.8 out of 10 on the CVSS severity scale, which is high. Our risk score for CVE-2009-2692 is 47 out of 100, which is Medium. Its action is "Plan remediation". Not confirmed as exploited yet, but serious or likely enough that it should not wait for a quiet month.

### Is CVE-2009-2692 being exploited?

It is not on the list of flaws known to be exploited today. The latest forecast puts the chance of it being used in the next 30 days at 15%. That can change at any time, which is why we keep watching.

### Which versions does CVE-2009-2692 affect?

For Linux kernel: 2.4.4 to before 2.4.37.5, 2.6.0 to before 2.6.30.5. The record lists 8 products in all, each with its versions, under "Who is affected" on this page.

### How do I fix CVE-2009-2692?

Install the update the vendor names in its advisory, linked first under "How do I fix" on this page. If you can't patch today, follow the vendor's mitigation and limit who can reach the affected system from the internet.

## Does CVE-2009-2692 affect you?

Precursor Intelligence keeps checking for you:

- **Tell us what you run.** Pick your software from a list, or let us work it out from your website.
- **We match it to every flaw.** Over 400,000 published flaws, checked against your list.
- **Ranked by real-world risk.** Every flaw gets a 0 to 100 risk score, kept up to date, led by evidence criminals are using it.
- **Told as soon as we know.** An alert by email, in the app or by webhook to your own tools.

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