Debian DSA-4465-1 : linux - security update (SACK Panic) (SACK Slowness)
High Nessus Plugin ID 125959
SynopsisThe remote Debian host is missing a security-related update.
DescriptionSeveral 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-2019-9500, CVE-2019-9503 Hugues Anguelkov discovered a buffer overflow and missing access validation in the Broadcom FullMAC wifi driver (brcmfmac), which a attacker on the same wifi network could use to cause denial of service or the execution of arbitrary code.
- 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 536 unless you know that your network requires a lower value.
- CVE-2019-11486 Jann Horn of Google reported numerous race conditions in the Siemens R3964 line discipline. A local user could use these to cause unspecified security impact. This module has therefore been disabled.
- CVE-2019-11599 Jann Horn of Google reported a race condition in the core dump implementation which could lead to a use-after-free. A local user could use this to read sensitive information, to cause a denial of service (memory corruption), or for privilege escalation.
- CVE-2019-11815 It was discovered that a use-after-free in the Reliable Datagram Sockets protocol could result in denial of service and potentially privilege escalation. This protocol module (rds) is not auto loaded on Debian systems, so this issue only affects systems where it is explicitly loaded.
- 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.
SolutionUpgrade the linux packages.
For the stable distribution (stretch), these problems have been fixed in version 4.9.168-1+deb9u3.