Last updated 4 July 2026
A flaw was found in the Linux kernels key management system where it was possible for an attacker to escalate privileges or crash the machine.
If a user key gets negatively instantiated, an error code is cached in the payload area. A negatively instantiated key may be then be positively instantiated by updating it with valid data. However, the ->update key type method must be aware that the error code may be there.
Key management subsystems can abused to escalate privileges through memory corruption.
Upstream: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=096fe9eaea40a17e125569f9e657e34cdb6d73bd
A flaw was found in the way pi to pi futex requeueing was handled.
A local unprivileged user can use this flaw to increase their privileges on the system.
Last updated 24 July 2024
Description of problem: The handling functions for sending and receiving messages, in rdspagecopyuser(), use the unchecked copyuserinatomic functions without any access checks on user-provided pointers. As a result, by passing a kernel address as an iovec base address in recvmsg-style calls, a local user can overwrite arbitrary kernel memory, which can easily be used to escalate privileges to root.
Introduced via 7875e18e (v2.6.30-rc1).
Acknowledgements:
Red Hat would like to thank Dan Rosenberg of Virtual Security Research for reporting this issue.
A flaw was found in the way Linux kernel's floppy driver treated userspace provided data in certain error code path while processing FDRAWCMD ioctl command. An local user with write access to /dev/fdX could use this flaw to kfree() arbitrary data. (CVE-2014-1737)
It was found that Linux kernel's floppy driver leaked internal kernel memory addresses to userspace during processing of FDRAWCMD ioctl command. An local user with write access to /dev/fdX could use this flaw to get information about kernel heap arrangment. (CVE-2014-1738)
An 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.
Acknowledgements:
Red Hat would like to thank Matthew Daley for reporting these issues.
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.
A weakness was found in the Linux ASLR implementation. Any user able to running 32-bit applications in a x86 machine can disable the ASLR by setting the RLIMITSTACK resource to unlimited.
External references:
http://hmarco.org/bugs/CVE-2016-3672-Unlimiting-the-stack-not-longer-disables-ASLR.html http://seclists.org/bugtraq/2016/Apr/34
Upstream fix:
http://git.kernel.org/cgit/linux/kernel/git/tip/tip.git/commit/?id=8b8addf891de8a00e4d39fc32f93f7c5eb8feceb
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=8b8addf891de8a00e4d39fc32f93f7c5eb8feceb
A flaw was found in the CXGB3 kernel driver when the network was considered congested. The kernel would incorrectly misinterpret the congestion as an error condition and incorrectly free/clean up the skb. When the device would then send the skb's queued, these structures would be referenced and may panic the system or allow an attacker to escalate privileges in a use-after-free scenario.
From the patch:
----
The cxgb3send() functions return NETXMIT values, which are positive integers values. So don't treat positive return values as an error. ----
Upstream commit: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=67f1aee6f45059fd6b0f5b0ecb2c97ad0451f6b3
CVE assignment: http://seclists.org/oss-sec/2016/q1/311
A vulnerability was found in Linux kernel. There is an information leak in file "sound/core/timer.c" of the latest mainline Linux kernel, the stack object “tread” has a total size of 32 bytes. It contains a 8-bytes padding, which is not initialized but sent to user via copytouser(), resulting a kernel leak.
fs/pipe.c in the Linux kernel before 4.5 does not limit the amount of unread data in pipes, which allows local users to cause a denial of service (memory consumption) by creating many pipes with non-default sizes.
Destroy of network interface with huge number of ipv4 addresses keeps rtnllock for a very long time (up to hour). It blocks many network related operations, including for example creation of new incoming ssh connections.
The problem is especially important for containers, container owner have enough permission to enable this trigger and then can block network access on whole host node.
Upstream fix:
http://git.kernel.org/cgit/linux/kernel/git/davem/net-next.git/commit/?id=fbd40ea0180a2d328c5adc61414dc8bab9335ce2
References:
http://seclists.org/oss-sec/2016/q1/643
CVE assignment:
http://seclists.org/oss-sec/2016/q1/647
A flaw was found in the USB-MIDI Linux kernel driver: a double-free error could be triggered for the 'umidi' object. An attacker with physical access to the system could use this flaw to escalate their privileges.
A vulnerabilty was found in the Linux kernels hiddev driver. An attacker with permissions to the USB HID device can call an ioctl with the HIDIOCGUSAGES or HIDIOCSUSAGES command, and passes a report id of HIDREPORTIDUNKNOWN range checks that would prevent oversize buffers being copied from userspace to kernel space were bypassed.
The kernel would loop on a a value passed by userspace and can copy memory outside of the intended range. This can corrupt memory located after the struct in memory, duplicating the kernel memory or crashing the system
Upstream patch:
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=93a2001bdfd5376c3dc2158653034c20392d15c5
A vulnerability in the handling of Transactional Memory on powerpc systems was found. An unprivileged local user can crash the kernel by starting a transaction, suspending it, and then calling any of the exec() class system calls.
Patch:
https://patchwork.ozlabs.org/patch/636776/
Test case:
https://patchwork.ozlabs.org/patch/636774/
CVE request:
http://seclists.org/oss-sec/2016/q2/595
Kernel panic is encountered when sctp stack receives duplicate asconf chunks.
Upstream commmit:
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=b69040d8e39f20d5215a03502a8e8b4c6ab78395
Last updated 24 July 2024
Description of the problem: For a TCP-style socket, while processing the COOKIEECHO chunk in sctpsfdo51Dce(), after it has passed a series of sanity check, a new association would be created in sctpunpackcookie(), but afterwards, some processing maybe failed, and sctpassociationfree() will be called to free the previously allocated association, in sctpassociationfree(), skackbacklog value is decremented for this socket, since the initial value for skackbacklog is 0, after the decrement, it will be 65535, a wrap-around problem happens, and if we want to establish new associations afterward in the same socket, ABORT would be triggered since sctp deem the accept queue as full.
A remote attacker can block further connection to the particular sctp server socket by sending a specially crafted sctp packet.
Upstream patch: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=d3217b15a19a4779c39b212358a5c71d725822ee
Acknowledgements:
Red Hat would like to thank Gopal Reddy Kodudula of Nokia Siemens Networks for reporting this issue.
A flaw was found in the way iommu mapping failures were handled in kvmiommumappages() function in the Linux kernel (introduced by the fix for CVE-2014-3601).
A privileged user in the guest could use this flaw to crash the host in case the guest has access to passed in device.
Introduced by: http://git.kernel.org/cgit/virt/kvm/kvm.git/commit/?id=350b8bdd689cd2ab2c67c8a86a0be86cfa0751a7
Upstream patch: http://git.kernel.org/cgit/virt/kvm/kvm.git/commit/?id=3d32e4dbe71374a6780eaf51d719d76f9a9bf22f
DISPUTED Multiple integer overflows in the lzo1xdecompresssafe function in lib/lzo/lzo1xdecompresssafe.c in the LZO decompressor in the Linux kernel before 3.15.2 allow context-dependent attackers to cause a denial of service (memory corruption) via a crafted Literal Run. NOTE: the author of the LZO algorithms says "the Linux kernel is not affected; media hype."
A NULL pointer dereference flaw was found in the way the Linux kernel's Stream Control Transmission Protocol (SCTP) implementation handled simultaneous connections between the same hosts. A remote attacker could use this flaw to crash the system.
arch/x86/kvm/vmx.c in the KVM subsystem in the Linux kernel before 3.17.2 on Intel processors does not ensure that the value in the CR4 control register remains the same after a VM entry, which allows host OS users to kill arbitrary processes or cause a denial of service (system disruption) by leveraging /dev/kvm access, as demonstrated by PRSETTSC prctl calls within a modified copy of QEMU.
It was reported [1] that iptables can allow protocols that do not have a protocol handler kernel module loaded.
Given following iptables ruleset: -P FORWARD DROP -A FORWARD -m sctp --dport 9 -j ACCEPT -A FORWARD -p tcp --dport 80 -j ACCEPT -A FORWARD -p tcp -m conntrack -m state ESTABLISHED,RELATED -j ACCEPT
One would assume that this allows SCTP on port 9 and TCP on port 80. Unfortunately, if the SCTP conntrack module is not loaded, this allows all SCTP communication to pass through, i.e. -p sctp -j ACCEPT
[1]: http://www.spinics.net/lists/netfilter-devel/msg33430.html
Last updated 24 July 2024
Last updated 24 July 2024
A flaw was found in the way iommu mapping failures were handled in kvmiommumappages() function in the Linux kernel. A privileged user in the guest could use this flaw to crash the host in case the guest has access to passed in device.
Acknowledgements:
Red Hat would like to thank Jack Morgenstein of Mellanox for reporting this issue; the security impact of this issue was discovered by Michael Tsirkin of Red Hat.
Last updated 24 July 2024
Last updated 24 July 2024
A vulnerability was found in the usbnet Linux kernel driver.
The bug allows physically proximate attackers to cause a denial of service (NULL pointer dereference and system crash) or possibly have other impact by inserting a USB device with an invalid USB descriptor.
Upstream fixes:
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=4d06dd537f95683aba3651098ae288b7cbff8274 https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=1666984c8625b3db19a9abc298931d35ab7bc64b
External references:
https://www.spinics.net/lists/netdev/msg367669.html https://bugzilla.novell.com/showbug.cgi?id=974418
Reference and CVE assignment:
http://seclists.org/oss-sec/2016/q2/19
An information leak vulnerability in rtnetlink subsystem in Linux kernel was found in "net/core/rtnetlink.c". The stack object "map" has a total size of 32 bytes. Its last 4 bytes are padding generated by compiler. These padding bytes are not initialized and sent out via nlaput().
Public via:
http://marc.info/?l=linux-kernel&m=146230821206492&w=2
http://marc.info/?l=linux-netdev&m=146230822606494&w=2
CVE-ID request and assignment:
http://seclists.org/oss-sec/2016/q2/234
http://seclists.org/oss-sec/2016/q2/237
Upstream patch:
https://git.kernel.org/cgit/linux/kernel/git/davem/net.git/commit/?id=5f8e44741f9f216e33736ea4ec65ca9ac03036e6
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=5f8e44741f9f216e33736ea4ec65ca9ac03036e6