A use after free issue was found in the way Linux kernel's KVM hypervisor implements its device control API. While creating a device via kvmioctlcreatedevice(), device holds a reference to a VM object, latter this reference is transferred to caller's file descriptor table. If such file descriptor was to be closed, reference count to the VM object could become zero, potentially leading to use-after-free issue latter.
A user/process could use this flaw to crash the guest VM resulting in DoS issue OR potentially gain privileged access to a system.
Upstream patch: --------------- -> https://git.kernel.org/linus/cfa39381173d5f969daf43582c95ad679189cbc9
Reference: ---------- -> https://www.openwall.com/lists/oss-security/2019/02/18/2
A flaw named SegmentSmack was found in the way the Linux kernel handled specially crafted TCP packets. A remote attacker could use this flaw to trigger time and calculation expensive calls to tcpcollapseofoqueue() and tcppruneofoqueue() functions by sending specially modified packets within ongoing TCP sessions which could lead to a CPU saturation and hence a denial of service on the system. Maintaining the denial of service condition requires continuous two-way TCP sessions to a reachable open port, thus the attacks cannot be performed using spoofed IP addresses.
A flaw named FragmentSmack was found in the way the Linux kernel handled reassembly of fragmented IPv4 and IPv6 packets. A remote attacker could use this flaw to trigger time and calculation expensive fragment reassembly algorithms by sending specially crafted packets which could lead to a CPU saturation and hence a denial of service on the system.
External References:
https://access.redhat.com/articles/3553061
https://www.kb.cert.org/vuls/id/641765
A fix is a merge commit in the Linux kernel tree:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c30f1fc041b74ecdb072dd44f858750414b8b19f
consisting of the following commits:
7969e5c40dfd04799d4341f1b7cd266b6e47f227 385114dec8a49b5e5945e77ba7de6356106713f4 fa0f527358bd900ef92f925878ed6bfbd51305cc
A flaw was found in the Linux kernels with commit b6a2fea39318 ("mm: variable length argument support", from July 19, 2007) but without commit da029c11e6b1 ("exec:Limit arg stack to at most 75% of STKLIM", from July 7, 2017). An integer overflow in the Linux kernel's createelftables() function. A local attacker can exploit this vulnerability via a SUID-root binary and obtain full root privileges.
Referenced commits: b6a2fea39318 ("mm: variable length argument support", from July 19, 2007) https://github.com/torvalds/linux/commit/b6a2fea39318e43fee84fa7b0b90d68bed92d2ba
da029c11e6b1 ("exec: Limit arg stack to at most 75% of STKLIM", from July 7, 2017) https://github.com/torvalds/linux/commit/da029c11e6b12f321f36dac8771e833b65cec962
Additional references: https://www.qualys.com/2018/09/25/cve-2018-14634/mutagen-astronomy-integer-overflow-linux-createelftables-cve-2018-14634.txt
A vulnerability was found in the fs/inode.c:inodeinitowner() function logic of the LInux kernel that allows local users to create files with an unintended group ownership and with group execution and SGID permission bits set, in a scenario where a directory is SGID and belongs to a certain group and is writable by a user who is not a member of this group. This can lead to excessive permissions granted in case when they should not.
An integer overflow flaw was found in the way the Linux kernel's networking subsystem processed TCP Selective Acknowledgment (SACK) segments. While processing SACK segments, the Linux kernel's socket buffer (SKB) data structure becomes fragmented. Each fragment is about TCP maximum segment size (MSS) bytes. To efficiently process SACK blocks, the Linux kernel merges multiple fragmented SKBs into one, potentially overflowing the variable holding the number of segments. A remote attacker could use this flaw to crash the Linux kernel by sending a crafted sequence of SACK segments on a TCP connection with small value of TCP MSS, resulting in a denial of service (DoS).
Last updated 24 July 2024
When BIG-IP 14.0.0-14.1.0.1, 13.0.0-13.1.1.4, 12.1.0-12.1.4, 11.6.1-11.6.3.4, and 11.5.2-11.5.8 are processing certain rare data sequences occurring in PPTP VPN traffic, the BIG-IP system may execute incorrect logic. The TMM may restart and produce a core file as a result of this condition. The BIG-IP system provisioned with the CGNAT module and configured with a virtual server using a PPTP profile is exposed to this vulnerability.
On BIG-IP 11.5.1-11.6.3, 12.1.0-12.1.3, 13.0.0-13.1.1.1, and 14.0.0-14.0.0.2, under certain conditions, the snmpd daemon may leak memory on a multi-blade BIG-IP vCMP guest when processing authorized SNMP requests.
An excessive resource consumption flaw was found in the way the Linux kernel's networking subsystem processed TCP segments. If the Maximum Segment Size (MSS) of a TCP connection was set to low values, such as 48 bytes, it can leave as little as 8 bytes for the user data, which significantly increases the Linux kernel's resource (CPU, Memory, and Bandwidth) utilization. A remote attacker could use this flaw to cause a denial of service (DoS) by repeatedly sending network traffic on a TCP connection with low TCP MSS.
By design, BIND is intended to limit the number of TCP clients that can be connected at any given time. The number of allowed connections is a tunable parameter which, if unset, defaults to a conservative value for most servers. Unfortunately, the code which was intended to limit the number of simultaneous connections contained an error which could be exploited to grow the number of simultaneous connections beyond this limit. Versions affected: BIND 9.9.0 -> 9.10.8-P1, 9.11.0 -> 9.11.6, 9.12.0 -> 9.12.4, 9.14.0. BIND 9 Supported Preview Edition versions 9.9.3-S1 -> 9.11.5-S3, and 9.11.5-S5. Versions 9.13.0 -> 9.13.7 of the 9.13 development branch are also affected. Versions prior to BIND 9.9.0 have not been evaluated for vulnerability to CVE-2018-5743.
An excessive resource consumption flaw was found in the way the Linux kernel's networking subsystem processed TCP Selective Acknowledgment (SACK) segments. While processing SACK segments, the Linux kernel's socket buffer (SKB) data structure becomes fragmented, which leads to increased resource utilization to traverse and process these fragments as further SACK segments are received on the same TCP connection. A remote attacker could use this flaw to cause a denial of service (DoS) by sending a crafted sequence of SACK segments on a TCP connection.
On BIG-IP 14.0.0-14.0.0.2, 13.0.0-13.1.1.1, or 12.1.0-12.1.3.7, or Enterprise Manager 3.1.1, when authenticated administrative users run commands in the Traffic Management User Interface (TMUI), also referred to as the BIG-IP Configuration utility, restrictions on allowed commands may not be enforced.
On BIG-IP 14.0.0-14.0.0.2, 13.0.0-13.1.1.1, or 12.1.0-12.1.3.7, when a virtual server using the inflate functionality to process a gzip bomb as a payload, the BIG-IP system will experience a fatal error and may cause the Traffic Management Microkernel (TMM) to produce a core file.
On F5 BIG-IP 14.0.0, 13.0.0-13.1.0, 12.1.0-12.1.3, or 11.5.1-11.6.3 specifically crafted HTTP responses, when processed by a Virtual Server with an associated QoE profile that has Video enabled, may cause TMM to incorrectly buffer response data causing the TMM to restart resulting in a Denial of Service.
On BIG-IP 14.0.x, 13.x, 12.x, and 11.x, Enterprise Manager 3.1.1, BIG-IQ 6.x, 5.x, and 4.x, and iWorkflow 2.x, the passphrases for SNMPv3 users and trap destinations that are used for authentication and privacy are not handled by the BIG-IP system Secure Vault feature; they are written in the clear to the various configuration files.
In BIG-IP 14.0.0-14.0.0.2 or 13.0.0-13.1.1.1 or Enterprise Manager 3.1.1, when authenticated administrative users run commands in the Traffic Management User Interface (TMUI), also referred to as the BIG-IP Configuration utility, restrictions on allowed commands may not be enforced.
On BIG-IP 14.0.0-14.0.0.2 or 13.0.0-13.1.1.1, undisclosed traffic patterns may lead to denial of service conditions for the BIG-IP system. The configuration which exposes this condition is the BIG-IP self IP address which is part of a VLAN group and has the Port Lockdown setting configured with anything other than "allow-all".
On BIG-IP 14.0.0-14.0.0.2, 13.0.0-13.1.1.1, or 12.1.0-12.1.3.6, malicious requests made to virtual servers with an HTTP profile can cause the TMM to restart. The issue is exposed with the non-default "normalize URI" configuration options used in iRules and/or BIG-IP LTM policies.
In BIG-IP 14.0.0-14.0.0.2, 13.1.0.4-13.1.1.1, or 12.1.3.4-12.1.3.6, If an MPTCP connection receives an abort signal while the initial flow is not the primary flow, the initial flow will remain after the closing procedure is complete. TMM may restart and produce a core file as a result of this condition.
In BIG-IP 14.0.0-14.0.0.2, 13.0.0-13.1.1.5, 12.1.0-12.1.4.1, and 11.2.1-11.6.3.2, an attacker sending specially crafted SSL records to a SSL Virtual Server will cause corruption in the SSL data structures leading to intermittent decrypt BADRECORDMAC errors. Clients will be unable to access the application load balanced by a virtual server with an SSL profile until tmm is restarted.
Last updated 24 July 2024
On BIG-IP versions 15.0.0-15.0.1.1, 14.1.0-14.1.2.2, 14.0.0-14.0.1, 13.1.0-13.1.3.1, 12.1.0-12.1.5, and 11.5.2-11.6.5.1, users with access to edit iRules are able to create iRules which can lead to an elevation of privilege, configuration modification, and arbitrary system command execution.
On BIG-IP 15.0.0-15.0.1, 14.1.0-14.1.2, 14.0.0-14.0.1, and 13.1.0-13.1.3.1, under certain conditions tmm may leak memory when processing packet fragments, leading to resource starvation.
On versions 15.0.0-15.0.1.1, 14.1.0-14.1.2.2, 14.0.0-14.0.1, 13.1.0-13.1.3.2, 12.1.0-12.1.5, and 11.5.2-11.6.5.1, BIG-IP virtual servers with Loose Initiation enabled on a FastL4 profile may be subject to excessive flow usage under undisclosed conditions.
On BIG-IP 15.0.0-15.0.1, 14.1.0-14.1.2, 14.0.0-14.0.1, 13.1.0-13.1.3.1, 12.1.0-12.1.5, and 11.5.1-11.6.5.1, undisclosed traffic flow may cause TMM to restart under some circumstances.
On BIG-IP 15.0.0-15.0.1, 14.1.0-14.1.0.5, 14.0.0-14.0.0.4, 13.1.0-13.1.1.5, 12.1.0-12.1.4.1, and 11.5.1-11.6.5, under certain conditions, TMM may consume excessive resources when processing traffic for a Virtual Server with the FIX (Financial Information eXchange) profile applied.
On versions 15.0.0-15.0.1, 14.0.0-14.1.2.2, and 13.1.0-13.1.3.1, TMM may restart on BIG-IP Virtual Edition (VE) when using virtio direct descriptors and packets 2 KB or larger.
On BIG-IP 15.0.0-15.0.1, 14.1.0-14.1.0.5, 14.0.0-14.0.0.4, and 13.1.0-13.1.1.4, the TMM process may produce a core file when an upstream server or cache sends the BIG-IP an invalid age header value.
On BIG-IP 14.1.0-14.1.2, 14.0.0-14.0.1, and 13.1.0-13.1.1, undisclosed HTTP requests may consume excessive amounts of systems resources which may lead to a denial of service.