--- title: "CVE-2007-3731\n | Ubuntu" description: Ubuntu is an open source software operating system that runs from the desktop, to the cloud, to all your internet connected things. url: https://ubuntu.com/security/CVE-2007-3731?format=md keywords: index, follow --- # CVE-2007-3731 Publication date 17 September 2007 Last updated 24 July 2024 --- Ubuntu priority **Low** [Why this priority?](https://ubuntu.com/security/cves/about#priority ) Toggle side navigation ## Description The Linux kernel 2.6.20 and 2.6.21 does not properly handle an invalid LDT segment selector in %cs (the xcs field) during ptrace single-step operations, which allows local users to cause a denial of service (NULL dereference and OOPS) via certain code that makes ptrace PTRACE\_SETREGS and PTRACE\_SINGLESTEP requests, related to the TRACE\_IRQS\_ON function, and possibly related to the arch\_ptrace function. ### From the Ubuntu Security Team Evan Teran discovered that the Linux kernel ptrace routines did not correctly handle certain requests robustly. Local attackers could exploit this to crash the system, causing a denial of service ## Status Show unmaintained releases | Package | Ubuntu Release | Status | | --- | --- | --- | | linux-source-2.6.15 | 6.06 LTS dapper | Fixed 2.6.15-29.60 | | linux-source-2.6.17 | 6.10 edgy | Fixed 2.6.17.1-12.41 | | linux-source-2.6.20 | 7.04 feisty | Fixed 2.6.20-16.32 | --- * [How can I get the fixes?](https://ubuntu.com/security/cves/about#security) * [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses) ## References * [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-3731) * [NVD](https://nvd.nist.gov/vuln/detail/CVE-2007-3731) * [Launchpad](https://launchpad.net/bugs/cve/CVE-2007-3731) * [Debian](https://security-tracker.debian.org/tracker/CVE-2007-3731) ### Related Ubuntu Security Notices (USN) + [USN-518-1](https://usn.ubuntu.com/USN-518-1) + linux-source-2.6.15, linux-source-2.6.17, linux-source-2.6.20 vulnerabilities + 25 September 2007 ### Other references *