Updated kernel packages that fix several security issues in the Red Hat Enterprise Linux 3 kernel are now available. This security advisory has been rated as having important security impact by the Red Hat Security Response Team. The Linux kernel handles the basic functions of the operating system.
The following security issues were fixed: The Vicam USB driver did not use the copy_from_user function to access userspace, crossing security boundaries. (CAN-2004-0075) The ext3 and jfs code did not properly initialize journal descriptor blocks. A privileged local user could read portions of kernel memory. (CAN-2004-0177) The terminal layer did not properly lock line discipline changes or pending IO. An unprivileged local user could read portions of kernel memory, or cause a denial of service (system crash). (CAN-2004-0814) A race condition was discovered. Local users could use this flaw to read the environment variables of another process that is still spawning via /proc/.../cmdline. (CAN-2004-1058) A flaw in the execve() syscall handling was discovered, allowing a local user to read setuid ELF binaries that should otherwise be protected by standard permissions. (CAN-2004-1073). Red Hat originally reported this as being fixed by RHSA-2004:549, but the associated fix was missing from that update. Keith Owens reported a flaw in the Itanium unw_unwind_to_user() function. A local user could use this flaw to cause a denial of service (system crash) on the Itanium architecture. (CAN-2005-0135) A missing Itanium syscall table entry could allow an unprivileged local user to cause a denial of service (system crash) on the Itanium architecture. (CAN-2005-0137) A flaw affecting the OUTS instruction on the AMD64 and Intel EM64T architectures was discovered. A local user could use this flaw to access privileged IO ports. (CAN-2005-0204) A flaw was discovered in the Linux PPP driver. On systems allowing remote users to connect to a server using ppp, a remote client could cause a denial of service (system crash). (CAN-2005-0384) A flaw in the Red Hat backport of NPTL to Red Hat Enterprise Linux 3 was discovered that left a pointer to a freed tty structure. A local user could potentially use this flaw to cause a denial of service (system crash) or possibly gain read or write access to ttys that should normally be prevented. (CAN-2005-0403) A flaw in fragment queuing was discovered affecting the netfilter subsystem. On systems configured to filter or process network packets (for example those configured to do firewalling), a remote attacker could send a carefully crafted set of fragmented packets to a machine and cause a denial of service (system crash). In order to sucessfully exploit this flaw, the attacker would need to know (or guess) some aspects of the firewall ruleset in place on the target system to be able to craft the right fragmented packets. (CAN-2005-0449) Missing validation of an epoll_wait() system call parameter could allow a local user to cause a denial of service (system crash) on the IBM S/390 and zSeries architectures. (CAN-2005-0736) A flaw when freeing a pointer in load_elf_library was discovered. A local user could potentially use this flaw to cause a denial of service (system crash). (CAN-2005-0749) A flaw was discovered in the bluetooth driver system. On system where the bluetooth modules are loaded, a local user could use this flaw to gain elevated (root) privileges. (CAN-2005-0750) In addition to the security issues listed above, there was an important fix made to the handling of the msync() system call for a particular case in which the call could return without queuing modified mmap()'ed data for file system update. (BZ 147969) Note: The kernel-unsupported package contains various drivers and modules that are unsupported and therefore might contain security problems that have not been addressed. Red Hat Enterprise Linux 3 users are advised to upgrade their kernels to the packages associated with their machine architectures/configurations Please note that the fix for CAN-2005-0449 required changing the external symbol linkages (kernel module ABI) for the ip_defrag() and ip_ct_gather_frags() functions. Any third-party module using either of these would also need to be fixed.