-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 ==================================================================== Red Hat Security Advisory Synopsis: Important: kernel-rt security update Advisory ID: RHSA-2019:1486-01 Product: Red Hat Enterprise Linux Advisory URL: https://access.redhat.com/errata/RHSA-2019:1486 Issue date: 2019-06-17 CVE Names: CVE-2019-11477 CVE-2019-11478 CVE-2019-11479 ==================================================================== 1. Summary: An update for kernel-rt is now available for Red Hat Enterprise Linux 7. 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 Realtime (v. 7) - noarch, x86_64 Red Hat Enterprise Linux for Real Time for NFV (v. 7) - noarch, x86_64 3. Description: The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements. Security Fix(es): * 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). (CVE-2019-11477) * Kernel: tcp: excessive resource consumption while processing SACK blocks allows remote denial of service (CVE-2019-11478) * Kernel: tcp: excessive resource consumption for TCP connections with low MSS allows remote denial of service (CVE-2019-11479) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section. 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/): 1719123 - CVE-2019-11477 Kernel: tcp: integer overflow while processing SACK blocks allows remote denial of service 1719128 - CVE-2019-11478 Kernel: tcp: excessive resource consumption while processing SACK blocks allows remote denial of service 1719129 - CVE-2019-11479 Kernel: tcp: excessive resource consumption for TCP connections with low MSS allows remote denial of service 6. Package List: Red Hat Enterprise Linux for Real Time for NFV (v. 7): Source: kernel-rt-3.10.0-957.21.3.rt56.935.el7.src.rpm noarch: kernel-rt-doc-3.10.0-957.21.3.rt56.935.el7.noarch.rpm x86_64: kernel-rt-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-debug-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-debug-debuginfo-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-debug-devel-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-debug-kvm-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-debug-kvm-debuginfo-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-debuginfo-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-debuginfo-common-x86_64-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-devel-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-kvm-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-kvm-debuginfo-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-trace-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-trace-debuginfo-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-trace-devel-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-trace-kvm-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-trace-kvm-debuginfo-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm Red Hat Enterprise Linux Realtime (v. 7): Source: kernel-rt-3.10.0-957.21.3.rt56.935.el7.src.rpm noarch: kernel-rt-doc-3.10.0-957.21.3.rt56.935.el7.noarch.rpm x86_64: kernel-rt-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-debug-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-debug-debuginfo-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-debug-devel-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-debuginfo-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-debuginfo-common-x86_64-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-devel-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-trace-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-trace-debuginfo-3.10.0-957.21.3.rt56.935.el7.x86_64.rpm kernel-rt-trace-devel-3.10.0-957.21.3.rt56.935.el7.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-2019-11477 https://access.redhat.com/security/cve/CVE-2019-11478 https://access.redhat.com/security/cve/CVE-2019-11479 https://access.redhat.com/security/updates/classification/#important https://access.redhat.com/security/vulnerabilities/tcpsack 8. Contact: The Red Hat security contact is . More contact details at https://access.redhat.com/security/team/contact/ Copyright 2019 Red Hat, Inc. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIVAwUBXQfxR9zjgjWX9erEAQhVbw/9EZjcbTKGqGgyVBrB3JvQ2iy/ad204ZOx oXE3qC5FuktU1dLha5pztyp6w3piInnU5LWN+9MqjjnYM/58VouvDyGvPaDSu43q MX4BJ/Dz7Nka5RrFGpsWsqcJJxbYtPgW7zy75WPs14t9rStlibs1RQoEwkkWH3+E bS3Zf143CpdMOczrvN1m2n43p0h69Bh3Q97qUtPthkL2RCpuSQJZDdok8k0BsCv7 Amu0rI9IhMmD3Ft2GPPW4vbHyFSG3yZNbujcGYbxPh+XrBSffs2cv8GlFK2upLn4 1H0uDz5zCrISs68W3UpoS/uUJ3mANFTj4MpBe/lHmZZHoGwF3UiyRm4AARhtcQX6 HL/GH3nJMPBUdM5kIlo2XR5rSK8kl0Df8+UShfS5EyOuttSZZsYHP9kT5ljojuNO a2W7Ypuw1yFyumPNmvNbcGrKpXMVlSXs2JHR0w0vYKkjHdAZfjMycSBLbEtWqih7 DPZzA3ui8e8Z/FqWpVjLI/2y3hwBJB/lXdHQGPk1Xv3u/La8HnUjyMzZPnOdMDiw NPxYF6dM/lOA2B2tpydBWt9w4LrbjIVb1J7TwtgiMjBP3SEuLKHI5DqDblTf5tmD tctoOasNFHvdVupJp/rXCEHPvVmMJBNhtPfDceKbHh/FgWEXmBr5lsts8Qc8Jmo2 eP/3LDZ4QgA=UQ0B -----END PGP SIGNATURE----- -- RHSA-announce mailing list RHSA-announce@redhat.com https://www.redhat.com/mailman/listinfo/rhsa-announce