Last updated 24 July 2024
Last updated 24 July 2024
Last updated 24 July 2024
If a single descriptor crosses a region, the second chunk length should be decremented by size translated so far, instead it includes the full descriptor length. A privileged guest user could use this flaw to crash the host or, potentially, corrupt host memory.
Upstream fix: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=bd97120fc3d1a11f3124c7c9ba1d91f51829eb85
Buffer overflow in the nfs4getacluncached function in fs/nfs/nfs4proc.c in the Linux kernel before 3.7.2 allows local users to cause a denial of service (memory corruption and system crash) or possibly have unspecified other impact via a getxattr system call for the system.nfs4acl extended attribute of a pathname on an NFSv4 filesystem.
It was reported [1] that perf would look for configuration files in /etc/perfconfig, ~/.perfconfig, and ./config. If ./config is not a perf configuration file, perf could fail or possibly do unexpected things. If a privileged user was tricked into running perf in a directory containing a malicious ./config file, it could possibly lead to the execution of arbitrary commands.
A patch is available [2].
[1] http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=632923 [2] http://marc.info/?l=linux-kernel&m=131256355026183
Access to /dev/cpu//msr was protected only using filesystem checks. A local uid 0 (root) user with all capabilities dropped could use this flaw to execute arbitrary code in kernel mode.
Upstream commit: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=c903f0456bc69176912dee6dd25c6a66ee1aed00
References: http://grsecurity.net/~spender/msr32.c
Last updated 24 July 2024
A flaw was found in the way xeniret() used userspace alterable %ds. An unprivileged local guest user in the 32-bit PV Xen domain could use this flaw to crash the guest or, potentially, escalate their privileges.
Acknowledgements:
This issue was discovered by Andrew Jones of Red Hat.
Last updated 24 July 2024
Buffer overflow in the VFAT filesystem implementation in the Linux kernel before 3.3 allows local users to gain privileges or cause a denial of service (system crash) via a VFAT write operation on a filesystem with the utf8 mount option, which is not properly handled during UTF-8 to UTF-16 conversion.
Last updated 24 July 2024
Last updated 24 July 2024
A flaw was found in the way Linux kernel's device-mapper subsystem, under certain conditions, interpreted data written to snapshot block devices. Snapshots are constructed from a single "cow" (copy-on-write) device that contains a mixture of data and metadata, and the bug involves a user writing a data block that is later incorrectly interpreted as metadata controlling how blocks are mapped.
An attacker could construct a mapping to read data from disk blocks in 'free space' that is normally inaccessible.
Please note that apart from having security consequences (data leak), this bug is also a data corruptor.
Acknowledgements:
Red Hat would like to thank Fujitsu for reporting this issue.
A flaw was found in the way ansi cprng implementation in the Linux kernel processed non-block size aligned requests. If several small requests are made that are less than the instances block size, the remainder for loop code doesn't increment randdatavalid in the last iteration, meaning that the last bytes in the randdata buffer gets reused on the subsequent smaller-than-a-block request for random data.
Acknowledgements:
Red Hat would like to thank Stephan Mueller for reporting this issue.
A flaw was found in the way Linux kernel's SCTP network protocol implementation handled duplicate cookies. A transient empty association is created while processing the duplicate cookie chunk that userspace could query, potentially leading to NULL pointer dereference. A remote attacker able to initiate SCTP connection to the system could use this flaw to create transient conditions that could lead to remote system crash if remote system user is querying SCTP connection info at the time these conditions exist.
Upstream fix: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=f2815633504b442ca0b0605c16bf3d88a3a0fcea
Last updated 24 July 2024
Last updated 24 July 2024
Alan Chester reported an issue with IPv6 on SCTP that IPsec traffic is not being encrypted, whereas on IPv4 it is. Setting up an AH + ESP transport does not seem to have the desired effect:
SCTP + IPv4:
22:14:20.809645 IP (tos 0x2,ECT(0), ttl 64, id 0, offset 0, flags [DF], proto AH (51), length 116) 192.168.0.2 > 192.168.0.5: AH(spi=0x00000042,sumlen=16,seq=0x1): ESP(spi=0x00000044,seq=0x1), length 72 22:14:20.813270 IP (tos 0x2,ECT(0), ttl 64, id 0, offset 0, flags [DF], proto AH (51), length 340) 192.168.0.5 > 192.168.0.2: AH(spi=0x00000043,sumlen=16,seq=0x1):
SCTP + IPv6:
22:31:19.215029 IP6 (class 0x02, hlim 64, next-header SCTP (132) payload length: 364) fe80::222:15ff:fe87:7fc.3333 > fe80::92e6:baff:fe0d:5a54.36767: sctp 1) [INIT ACK] [init tag: 747759530] [rwnd: 62464] [OS: 10] [MIS: 10]
References: https://bugzilla.kernel.org/showbug.cgi?id=24412
Upstream fix: http://git.kernel.org/cgit/linux/kernel/git/davem/net.git/commit/?id=95ee62083cb6453e056562d91f597552021e6ae7
An SCTP server doing ASCONF will panic on malformed INIT ping-of-death in the form of:
------------ INIT[PARAM: SETPRIMARYIP] ------------>
A remote attacker could use this flaw to crash the system by sending a maliciously prepared SCTP packet in order to trigger a NULL pointer dereference on the server.
Upstream patch:
https://git.kernel.org/cgit/linux/kernel/git/davem/net.git/commit/?id=e40607cbe270a9e8360907cb1e62ddf0736e4864
Acknowledgements:
This issue was discovered by Liu Wei of Red Hat.
It was found that Linux kernel's sctp stack is prone to remotely triggerable memory pressure issue caused by excessive queueing.
A remote attacker could use this flaw to cause denial-of-service conditions on the system.
Upstream commmit:
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=26b87c7881006311828bb0ab271a551a62dcceb4
It was found that reporting emulation failures to user space could lead to either a local (CVE-2014-7842) or a L2->L1 (CVE-2010-5313) denial of service. In the case of a local denial of service, an attacker must have access to the MMIO area or be able to access an I/O port. Please note that on certain systems, HPET is mapped to userspace as part of vdso (vvar) and thus an unprivileged user may generate MMIO transactions (and enter the emulator) this way.
Last updated 24 July 2024
journalunmapbuffer()'s zapbuffer: code clears a lot of buffer head state ala discardbuffer(), but does not touch Delay or Unwritten as discardbuffer() does.
This can be problematic in some areas of the ext4 code which assume that if they have found a buffer marked unwritten or delay, then it's a live one. They do not check whether a buffer is mapped, so jbd2's partial teardown can be problematic if they assume that this buffer head is still valid.
(Mounting without a journal also avoids the bug, because with no journal we go to unmapbuffer(), which does the right thing).
An unprivileged local user could use this flaw to crash the system.
Florian Weimer of the Red Hat Product Security Team discovered that hypervkvpd would exit when it processed a spoofed Netlink packet that had been sent from an untrusted local user, in the following code:
len = recvfrom(fd, kvprecvbuffer, sizeof(kvprecvbuffer), 0, addrp, &addrl);
if (len < 0 || addr.nlpid) { syslog(LOGERR, "recvfrom failed; pid:%u error:%d %s", addr.nlpid, errno, strerror(errno)); close(fd); return -1; }
Acknowledgements:
This issue was discovered by Florian Weimer of the Red Hat Product Security Team.
A flaw was found in the way skbrecvdatagram() processed skbs with no payload when MSGPEEK was requested. An unprivileged local user could use this flaw to cause local denial of service.
Upstream commit: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=77c1090
References: http://seclists.org/oss-sec/2013/q1/310
Buffer overflow in the ozcdevwrite function in drivers/staging/ozwpa ...
Last updated 24 July 2024
Last updated 24 July 2024
Last updated 24 July 2024