Description
The copy_from_user function in the uaccess code in Linux kernel 2.6 before 2.6.19-rc1, when running on s390, does not properly clear a kernel buffer, which allows local user space programs to read portions of kernel memory by "appending to a file from a bad address," which triggers a fault that prevents the unused memory from being cleared in the kernel buffer.
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 3.1 | kernel-source-2.4.27 | 2.4.27-10sarge5 | DSA-1237-1 |
| Debian 3.1 | kernel-source-2.6.8 | 2.6.8-16sarge6 | DSA-1233-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 4 | kernel +8 | 2.6.9-42.0.8.EL | RHSA-2007:0014 |
| RHEL 3 | kernel +8 | 2.4.21-47.0.1.EL | RHSA-2006:0710 |
Advisories 4
- RHSA-2007:0014 Red Hat Security Advisory: kernel security update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- RHSA-2006:0710 Red Hat Security Advisory: kernel security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- DSA-1237-1 kernel-source-2.4.27 - several Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-1233-1 kernel-source-2.6.8 - several Debian Security (DSA / DLA) · Mar 9, 2026
References
- [linux-kernel] 20061105 Linux 2.6.16.31-rc1 mailing-list
- oval:org.mitre.oval:def:9885 vdb-entry signature
- SUSE-SA:2006:079 vendor-advisory
- kernel-copyfromuser-information-disclosure(29378) vdb-entry
- 20379 vdb-entry
- RHSA-2007:0014 vendor-advisory
- ADV-2006-3938 vdb-entry
- http://support.avaya.com/elmodocs2/security/ASA-2007-063.htm
- DSA-1237 vendor-advisory
- 24206 third-party-advisory
- 1017090 vdb-entry
- 23474 third-party-advisory
- 23064 third-party-advisory
- DSA-1233 vendor-advisory
- 23370 third-party-advisory
- 23997 third-party-advisory
- http://support.avaya.com/elmodocs2/security/ASA-2006-254.htm
- http://www.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=52149ba6b0ddf3e9d965257cc0513193650b3ea8
- 22497 third-party-advisory
- RHSA-2006:0710 vendor-advisory
- 23395 third-party-advisory
- 22289 third-party-advisory