A UNIX Symbolic Link (Symlink) Following vulnerability in chkstat of SUSE Linux Enterprise Server 12, SUSE Linux Enterprise Server 15, SUSE Linux Enterprise Server 11 set permissions intended for specific binaries on other binaries because it erroneously followed symlinks. The symlinks can't be controlled by attackers on default systems, so exploitation is difficult. This issue affects: SUSE Linux Enterprise Server 12 permissions versions prior to 2015.09.28.1626-17.27.1. SUSE Linux Enterprise Server 15 permissions versions prior to 20181116-9.23.1. SUSE Linux Enterprise Server 11 permissions versions prior to 2013.1.7-0.6.12.1.

The session-restore feature in Mozilla Firefox before 28.0 and SeaMonkey before 2.25 does not consider the Content Security Policy of a data: URL, which makes it easier for remote attackers to conduct cross-site scripting (XSS) attacks via a crafted document that is accessed after a browser restart.

Last updated 24 July 2024

An information leak flaw was found in the way way segmentation was performed on skbs originated from vhost-net when zerocopy feature was enabled. Once the source skb is consumed, ubuf destructor is called and potentially releases the corresponding userspace buffers, which can then for example be repurposed, while the destination skb could still be pointing to the them.

Acknowledgements:

This issue was discovered by Michael S. Tsirkin of Red Hat.

Description of problem: On x86-64, a 32-bit process (TIFIA32) can switch to 64-bit mode with ljmp, and then use the "syscall" instruction to make a 64-bit system call. A 64-bit process make a 32-bit system call with int $0x80.

In both these cases, auditsyscallentry() will use the wrong system call number table and the wrong system call argument registers. This could be used to circumvent a syscall audit configuration that filters based on the syscall numbers or argument details.

References: http://scary.beasts.org/security/CESA-2009-001.html http://scary.beasts.org/security/CESA-2009-004.html https://bugzilla.redhat.com/showbug.cgi?id=487255 http://lkml.org/lkml/2009/2/27/451 summary http://lkml.org/lkml/2009/2/27/452 syscall-audit

Unspecified vulnerability in xscreensaver 4.12, and possibly other versions, allows attackers to cause xscreensaver to crash via unspecified vectors "while verifying the user-password."

The PPP wvdial.lxdialog script in wvdial 1.4 and earlier creates a .config file with world readable permissions, which allows a local attacker in the dialout group to access login and password information.

aaabase in SuSE Linux 6.3, and cron.daily in earlier versions, allow local users to delete arbitrary files by creating files whose names include spaces, which are then incorrectly interpreted by aaabase when it deletes expired files from the /tmp directory.

xtvscreen in SuSE Linux 6.0 allows local users to overwrite arbitrary files via a symlink attack on the pic000.pnm file.

It was discovered that the Invariance Weakness of the RC4 stream cipher could be used to recover plaintext from a TLS connection, when RC4 encryption is used.

"The Invariance Weakness is an L-shape key pattern in RC4 keys, which once it exists in an RC4 key, preserves part of the state permutation intact throughout the initialization process. This intact part includes the least significant bits of the permutation, when processed by the PRGA algorithm, determines the least significant bits of the allegedly pseudo-random output stream along a long prefix of the stream."

This can lead to significant leakage of plaintext bytes from the ciphertext.

External Reference:

http://www.imperva.com/docs/HIIAttackingSSLwhenusingRC4.pdf

Last updated 24 July 2024

A flaw was found in the way the Linux kernel's floppy driver handled user space provided data in certain error code paths while processing FDRAWCMD IOCTL commands. A local user with write access to /dev/fdX could use this flaw to free (using the kfree() function) arbitrary kernel memory. (CVE-2014-1737, Important) It was found that the Linux kernel's floppy driver leaked internal kernel memory addresses to user space during the processing of the FDRAWCMD IOCTL command. A local user with write access to /dev/fdX could use this flaw to obtain information about the kernel heap arrangement. (CVE-2014-1738, Low) Note: A local user with write access to /dev/fdX could use these two flaws (CVE-2014-1737 in combination with CVE-2014-1738) to escalate their privileges on the system.

kernel/auditsc.c in the Linux kernel through 3.14.5, when CONFIGAUDITSYSCALL is enabled with certain syscall rules, allows local users to obtain potentially sensitive single-bit values from kernel memory or cause a denial of service (OOPS) via a large value of a syscall number.

It was found that espfix funcionality (when returning to userspace with a 16 bit stack, the CPU will not restore the high word of esp for us on executing iret and thus potentially leaks kernel addresses; espfix fixes this) does not work for 32-bit KVM paravirt guests.

A local unprivileged user could potentially use this flaw to leak kernel stack addresses.

Proposed upstream patch: http://www.spinics.net/lists/kvm/msg111458.html

Acknowledgements:

Red Hat would like to thank Andy Lutomirski for reporting this issue.

Last updated 24 July 2024

Last updated 24 July 2024

Last updated 24 July 2024

Last updated 24 July 2024

Last updated 24 July 2024

Last updated 24 July 2024

Last updated 24 July 2024

Description of problem: This problem was originally tracked down by Brad Spengler.

When calling wireless ioctls, if a driver does not correctly validate/shrink iwp->length, the resulting copytouser can leak up to 64K of kernel heap contents.

It seems that this is triggerable[1] in 2.6.32 at least on ath5k, but I was not able to track down how. The twisty maze of ioctl handlers stumped me. :) Other drivers I checked did not appear to have any problems, but the potential remains. I'm not sure if this patch is the right approach; it was fixed differently[2] in grsecurity.

[1] http://forums.grsecurity.net/viewtopic.php?f=3&t=2290&start=0 [2] http://grsecurity.net/~spender/wireless-infoleak-fix2.patch

Discussion: http://lkml.org/lkml/2010/8/27/413

A flaw was found in the way Linux kernel's Journaling Block Device (JBD) handled invalid log first block value. An attacker able to mount malicious ext3 or ext4 image could use this flaw to crash the system.

Upstream commit: 8762202dd0d6e46854f786bdb6fb3780a1625efe

Description of problem: The SNDRVHDSPIOCTLGETCONFIGINFO ioctl in hdsp.c allows unprivileged users to read uninitialized kernel stack memory, because several fields of the hdspmconfiginfo structs declared on the stack are not altered or zeroed before being copied back to the user.

Reference: http://www.openwall.com/lists/oss-security/2010/10/06/6 http://lkml.org/lkml/2010/9/25/41

Acknowledgements:

Red Hat would like to thank Dan Rosenberg for reporting this issue.

Description of problem: The FBIOGETVBLANK device ioctl in sismain.c allows unprivileged users to read 16 bytes of uninitialized stack memory, because the 'reserved' member of the fbvblank struct declared on the stack is not altered or zeroed before being copied back to the user.

Reference: http://www.openwall.com/lists/oss-security/2010/10/06/6 http://lkml.indiana.edu/hypermail//linux/kernel/1009.1/03385.html

Acknowledgements:

Red Hat would like to thank Dan Rosenberg for reporting this issue.

Description of problem: The compat ipc functions allow unprivileged users to read uninitialized stack memory, because some of the structures used and declared on the stack are not altered or zeroed before being copied back to the user.

Reference: http://www.openwall.com/lists/oss-security/2010/10/07/1 http://lkml.org/lkml/2010/10/6/492

Acknowledgements:

Red Hat would like to thank Dan Rosenberg for reporting this issue.

Description of problem: The "mem" array used as scratch space for socket filters is not initialized, allowing unprivileged users to leak kernel stack bytes.

http://www.spinics.net/lists/netdev/msg146361.html http://lists.grok.org.uk/pipermail/full-disclosure/2010-November/077321.html

Acknowledgements:

Red Hat would like to thank Dan Rosenberg for reporting this issue.

Description of problem: The semctl syscall has several code paths that lead to the leakage of uninitialized kernel stack memory (namely the IPCINFO, SEMINFO, IPCSTAT, and SEMSTAT commands) during the use of the older, obsolete version of the semidds struct. The copysemidtouser() function declares a semidds struct on the stack and copies it back to the user without initializing or zeroing the 'sembase', 'sempending', 'sempendinglast', and 'undo' pointers, allowing the leakage of 16 bytes of kernel stack memory. The code is still reachable on 32-bit systems - when calling semctl() newer glibc's automatically OR the IPC command with the IPC64 flag, but invoking the syscall directly allows users to use the older versions of the struct.

Reference: http://www.openwall.com/lists/oss-security/2010/10/06/6 http://www.spinics.net/lists/mm-commits/msg80234.html

Acknowledgements:

Red Hat would like to thank Dan Rosenberg for reporting this issue.

Description of problem: The old shm interface allows unprivileged users to read uninitialized stack memory, because shmidds structure declared on the stack is not altered or zeroed before being copied back to the user.

Reference: http://www.openwall.com/lists/oss-security/2010/10/07/1 http://lkml.org/lkml/2010/10/6/454

Acknowledgements:

Red Hat would like to thank Vasiliy Kulikov of Openwall and Kees Cook for reporting this issue.

Description of problem: The SNDRVHDSPIOCTLGETCONFIGINFO ioctl in hdspm.c allows unprivileged users to read uninitialized kernel stack memory, because several fields of the hdspmconfiginfo structs declared on the stack are not altered or zeroed before being copied back to the user.

Reference: http://www.openwall.com/lists/oss-security/2010/10/06/6 http://lkml.org/lkml/2010/9/25/41

Acknowledgements:

Red Hat would like to thank Dan Rosenberg for reporting this issue.