Description
The do_task_stat function in fs/proc/array.c in the Linux kernel before 2.6.39-rc1 does not perform an expected uid check, which makes it easier for local users to defeat the ASLR protection mechanism by reading the start_code and end_code fields in the /proc/#####/stat file for a process executing a PIE binary.
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.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 6.0 | linux-2.6 | 2.6.32-34squeeze1 | DSA-2240-1 |
| Debian 5.0 | linux-2.6 | 2.6.26-26lenny3 | DSA-2264-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 6 | perf +13 | 2.6.32-71.29.1.el6 | RHSA-2011:0498 |
| RHEL 5 | kernel +11 | 2.6.18-238.12.1.el5 | RHSA-2011:0833 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat MRG 1 | perf +10 | 2.6.33.9-rt31.64.el5rt | RHSA-2011:0500 |
Advisories 5
- RHSA-2011:0833 Red Hat Security Advisory: kernel security and bug fix update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- RHSA-2011:0500 Red Hat Security Advisory: kernel-rt security and bug fix update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- RHSA-2011:0498 Red Hat Security Advisory: kernel security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- DSA-2240-1 linux-2.6 - several issues Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-2264-1 linux-2.6 - several issues Debian Security (DSA / DLA) · Mar 9, 2026
References
- [mm-commits] 20110314 + proc-protect-mm-start_code-end_code-in-proc-pid-stat.patch added to -mm tree mailing-list
- https://bugzilla.redhat.com/show_bug.cgi?id=684569
- 47791 vdb-entry
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=5883f57ca0008ffc93e09cbb9847a1928e50c6f3
- http://www.kernel.org/pub/linux/kernel/v2.6/testing/v2.6.39/ChangeLog-2.6.39-rc1
- RHSA-2011:0833 vendor-advisory
- http://downloads.avaya.com/css/P8/documents/100145416
- [linux-kernel] 20110311 [PATCH] proc: protect mm start_code/end_code in /proc/pid/stat mailing-list