Debian Security Advisory

DLA-1823-1 linux -- LTS security update

Date Reported:
17 Jun 2019
Affected Packages:
Security database references:
In Mitre's CVE dictionary: CVE-2019-3846, CVE-2019-5489, CVE-2019-10126, CVE-2019-11477, CVE-2019-11478, CVE-2019-11479, CVE-2019-11810, CVE-2019-11833, CVE-2019-11884.
More information:

Several vulnerabilities have been discovered in the Linux kernel that may lead to a privilege escalation, denial of service or information leaks.

  • CVE-2019-3846, CVE-2019-10126

    huangwen reported multiple buffer overflows in the Marvell wifi (mwifiex) driver, which a local user could use to cause denial of service or the execution of arbitrary code.

  • CVE-2019-5489

    Daniel Gruss, Erik Kraft, Trishita Tiwari, Michael Schwarz, Ari Trachtenberg, Jason Hennessey, Alex Ionescu, and Anders Fogh discovered that local users could use the mincore() system call to obtain sensitive information from other processes that access the same memory-mapped file.

  • CVE-2019-11477

    Jonathan Looney reported that a specially crafted sequence of TCP selective acknowledgements (SACKs) allows a remotely triggerable kernel panic.

  • CVE-2019-11478

    Jonathan Looney reported that a specially crafted sequence of TCP selective acknowledgements (SACKs) will fragment the TCP retransmission queue, allowing an attacker to cause excessive resource usage.

  • CVE-2019-11479

    Jonathan Looney reported that an attacker could force the Linux kernel to segment its responses into multiple TCP segments, each of which contains only 8 bytes of data, drastically increasing the bandwidth required to deliver the same amount of data.

    This update introduces a new sysctl value to control the minimal MSS (net.ipv4.tcp_min_snd_mss), which by default uses the formerly hard-coded value of 48. We recommend raising this to 512 unless you know that your network requires a lower value. (This value applies to Linux 3.16 only.)

  • CVE-2019-11810

    It was discovered that the megaraid_sas driver did not correctly handle a failed memory allocation during initialisation, which could lead to a double-free. This might have some security impact, but it cannot be triggered by an unprivileged user.

  • CVE-2019-11833

    It was discovered that the ext4 filesystem implementation writes uninitialised data from kernel memory to new extent blocks. A local user able to write to an ext4 filesystem and then read the filesystem image, for example using a removable drive, might be able to use this to obtain sensitive information.

  • CVE-2019-11884

    It was discovered that the Bluetooth HIDP implementation did not ensure that new connection names were null-terminated. A local user with CAP_NET_ADMIN capability might be able to use this to obtain sensitive information from the kernel stack.

For Debian 8 Jessie, these problems have been fixed in version 3.16.68-2.

We recommend that you upgrade your linux packages.

Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: