Description
The ACPI subsystem in the Linux kernel before 2.6.36.2 uses 0222 permissions for the debugfs custom_method file, which allows local users to gain privileges by placing a custom ACPI method in the ACPI interpreter tables, related to the acpi_debugfs_init function in drivers/acpi/debugfs.c.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat MRG 1 | perf +10 | 2.6.33.7-rt29.55.el5rt | RHSA-2011:0330 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Exploit-DB 1
- Linux Kernel < 2.6.37-rc2 - 'ACPI custom_method' Local Privilege Escalation EDB-15774 · local · Dec 18, 2010 · verified
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 1
- RHSA-2011:0330 Red Hat Security Advisory: kernel-rt security and bug fix update Red Hat Security Advisories (RHSA) · Jan 14, 2026
References
- https://bugzilla.redhat.com/show_bug.cgi?id=663542
- 42778 third-party-advisory
- SUSE-SA:2011:001 vendor-advisory
- 45408 vdb-entry
- SUSE-SA:2011:007 vendor-advisory
- ADV-2011-0298 vdb-entry
- http://www.kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.36.2
- [oss-security] 20101215 CVE Request: local privilege escalation via /sys/kernel/debug/acpi/custom_method mailing-list
- ADV-2011-0012 vdb-entry
- [oss-security] 20101215 Re: CVE Request: local privilege escalation via /sys/kernel/debug/acpi/custom_method mailing-list
- 15774 exploit
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=ed3aada1bf34c5a9e98af167f125f8a740fc726a
- kernel-debugfs-privilege-esc(64155) vdb-entry