-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 ==================================================================== Red Hat Security Advisory Synopsis: Important: kernel security and bug fix update Advisory ID: RHSA-2018:2933-01 Product: Red Hat Enterprise Linux Advisory URL: https://access.redhat.com/errata/RHSA-2018:2933 Issue date: 2018-10-16 CVE Names: CVE-2018-5390 CVE-2018-5391 CVE-2018-10675 CVE-2018-14634 ==================================================================== 1. Summary: An update for kernel is now available for Red Hat Enterprise Linux 6.5 Advanced Update Support. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section. 2. Relevant releases/architectures: Red Hat Enterprise Linux Server AUS (v. 6.5) - noarch, x86_64 Red Hat Enterprise Linux Server Optional AUS (v. 6.5) - x86_64 3. Description: The kernel packages contain the Linux kernel, the core of any Linux operating system. Security Fix(es): * 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 tcp_collapse_ofo_queue() and tcp_prune_ofo_queue() 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. (CVE-2018-5390) * 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 algorithm by sending specially crafted packets which could lead to a CPU saturation and hence a denial of service on the system. (CVE-2018-5391) * kernel: mm: use-after-free in do_get_mempolicy function allows local DoS or other unspecified impact (CVE-2018-10675) * kernel: Integer overflow in Linux's create_elf_tables function (CVE-2018-14634) For more details about the security issue(s), including the impact, a CVSS score, and other related information, refer to the CVE page(s) listed in the References section. Red Hat would like to thank Juha-Matti Tilli (Aalto University - Department of Communications and Networking and Nokia Bell Labs) for reporting CVE-2018-5390 and CVE-2018-5391 and Qualys Research Labs for reporting CVE-2018-14634. Bug Fix(es): * Previously, invalid headers in the sk_buff struct led to an indefinite loop in the tcp_collapse() function. As a consequence, the system became unresponsive. This update backports the upstream changes that remove the problematic code in tcp_collapse(). As a result, the system no longer hangs in the described scenario. (BZ#1619630) * After updating the system to prevent the L1 Terminal Fault (L1TF) vulnerability, only one thread was detected on systems that offer processing of two threads on a single processor core. With this update, the "__max_smt_threads()" function has been fixed. As a result, both threads are now detected correctly in the described situation. (BZ#1625333) * Previously, a kernel panic occurred when the kernel tried to make an out of bound access to the array that describes the L1 Terminal Fault (L1TF) mitigation state on systems without Extended Page Tables (EPT) support. This update extends the array of mitigation states to cover all the states, which effectively prevents out of bound array access. Also, this update enables rejecting invalid, irrelevant values, that might be erroneously provided by the userspace. As a result, the kernel no longer panics in the described scenario. (BZ#1629632) 4. Solution: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 The system must be rebooted for this update to take effect. 5. Bugs fixed (https://bugzilla.redhat.com/): 1575065 - CVE-2018-10675 kernel: mm: use-after-free in do_get_mempolicy function allows local DoS or other unspecified impact 1601704 - CVE-2018-5390 kernel: TCP segments with random offsets allow a remote denial of service (SegmentSmack) 1609664 - CVE-2018-5391 kernel: IP fragments with random offsets allow a remote denial of service (FragmentSmack) 1624498 - CVE-2018-14634 kernel: Integer overflow in Linux's create_elf_tables function 6. Package List: Red Hat Enterprise Linux Server AUS (v. 6.5): Source: kernel-2.6.32-431.93.2.el6.src.rpm noarch: kernel-abi-whitelists-2.6.32-431.93.2.el6.noarch.rpm kernel-doc-2.6.32-431.93.2.el6.noarch.rpm kernel-firmware-2.6.32-431.93.2.el6.noarch.rpm x86_64: kernel-2.6.32-431.93.2.el6.x86_64.rpm kernel-debug-2.6.32-431.93.2.el6.x86_64.rpm kernel-debug-debuginfo-2.6.32-431.93.2.el6.x86_64.rpm kernel-debug-devel-2.6.32-431.93.2.el6.x86_64.rpm kernel-debuginfo-2.6.32-431.93.2.el6.x86_64.rpm kernel-debuginfo-common-x86_64-2.6.32-431.93.2.el6.x86_64.rpm kernel-devel-2.6.32-431.93.2.el6.x86_64.rpm kernel-headers-2.6.32-431.93.2.el6.x86_64.rpm perf-2.6.32-431.93.2.el6.x86_64.rpm perf-debuginfo-2.6.32-431.93.2.el6.x86_64.rpm python-perf-debuginfo-2.6.32-431.93.2.el6.x86_64.rpm Red Hat Enterprise Linux Server Optional AUS (v. 6.5): Source: kernel-2.6.32-431.93.2.el6.src.rpm x86_64: kernel-debug-debuginfo-2.6.32-431.93.2.el6.x86_64.rpm kernel-debuginfo-2.6.32-431.93.2.el6.x86_64.rpm kernel-debuginfo-common-x86_64-2.6.32-431.93.2.el6.x86_64.rpm perf-debuginfo-2.6.32-431.93.2.el6.x86_64.rpm python-perf-2.6.32-431.93.2.el6.x86_64.rpm python-perf-debuginfo-2.6.32-431.93.2.el6.x86_64.rpm These packages are GPG signed by Red Hat for security. Our key and details on how to verify the signature are available from https://access.redhat.com/security/team/key/ 7. References: https://access.redhat.com/security/cve/CVE-2018-5390 https://access.redhat.com/security/cve/CVE-2018-5391 https://access.redhat.com/security/cve/CVE-2018-10675 https://access.redhat.com/security/cve/CVE-2018-14634 https://access.redhat.com/security/updates/classification/#important https://access.redhat.com/articles/3553061 https://access.redhat.com/security/vulnerabilities/mutagen-astronomy 8. Contact: The Red Hat security contact is . More contact details at https://access.redhat.com/security/team/contact/ Copyright 2018 Red Hat, Inc. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIVAwUBW8Y0SdzjgjWX9erEAQgXbg/+LgFr9timcVIKvpoxlH9X1Wl/Lp5GBlDY V3bnym0hZYuR3t3fHD5LyUrYuvS6uNhgmt4JrlH241oaJZElAOMt5KTjZmwZ+DI/ yR26knby+u9/ftqoYSGdXspM5B3902syvgGY5IR2AgeUuX/K1Onw9M8dh2H2WRoF TnANdLyx2mOHlDdTPKscszHIn+gkLkv6OW/So7qrObJzcHVsteHIEP70zL/DrMeZ wfjW6nKzN4kOtpmtBYXdw4dRB+XAfCucVa9HH43TFJuMaCqlFFL97uPRuaKqNUZt pQYur7Awt+AefL4ZMHxL4sZq1T6AqkNriU1hPUEc1FIrOqSjH00m2/niUZh6GByX 370txawJVi5pU3l0LSR+bwCQa4ocfLfqcyyIHpQxnN8JWcFm4yZo9sGiGkjlxC8+ yzRhKJOXr4CZlpyVD+MHwGSh3XrIZ6OGxcj/JA25RrYl/hizMalV3hPIiajm3037 txF8VJJLPUfC8c4IMdmcLNLXIJfSSCxqyUJTXqbS2qurxhldWUzc4Gkjqbxzl3rx 72WTmj8VVE57FLjZjoj48e6w/siId8D7w5vKcdirQQskw2He5SwmJbYeTD/nnxiz lXyTlP5SlVX14CBc7Khfsssa1z6YRWSzD5OIjyJeN7NYTPouqWuvM74K8ma7ZPvZ AH0fjSvMopwn23 -----END PGP SIGNATURE----- -- RHSA-announce mailing list RHSA-announce@redhat.com https://www.redhat.com/mailman/listinfo/rhsa-announce