When IP packet fragmentation is ON, IP Identification(ID) field of the IP header is used, during packet reassembly on the destination host, to identify fragments which belong to the same packet. IP ID field is required to be unique and same across all fragments of an IP packet. IP packet fragments are identified by a tuple with following fields (source address|destination address|protocol|IP-ID) The Linux kernel derived this IP ID field from partial kernel space address returned by net_hash_mix() function, which is then used with a hash function to compute the IP ID field. A remote user could observe this IP ID field to deduce the hash key used to derive its value. This could enable a remote user to track particular Linux devices. Upstream fix: ------------- -> https://git.kernel.org/linus/df453700e8d81b1bdafdf684365ee2b9431fb702 Issue introduced by: -------------------- -> https://git.kernel.org/linus/b6a7719aedd7e5c0f2df7641aa47386111682df4 -> https://git.kernel.org/linus/5a352dd0a3aac03b443c94828dfd7144261c8636
Created kernel tracking bugs for this issue: Affects: fedora-all [bug 1729932]
External References: https://arxiv.org/pdf/1906.10478.pdf
Statement: This issue does not affect the versions of Linux kernel as shipped with Red Hat Enterprise Linux 5 and Red Hat Enterprise Linux 6. This issue affects the version of Linux kernel as shipped with Red Hat Enterprise Linux 7, 8 and Red Hat Enterprise MRG 2. Future kernel updates for Red Hat Enterprise Linux 7, 8 and Red Hat Enterprise MRG 2 may address this issue.
This issue has been addressed in the following products: Red Hat Enterprise Linux 8 Via RHSA-2019:3309 https://access.redhat.com/errata/RHSA-2019:3309
This issue has been addressed in the following products: Red Hat Enterprise Linux 8 Via RHSA-2019:3517 https://access.redhat.com/errata/RHSA-2019:3517
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s): https://access.redhat.com/security/cve/cve-2019-10638
This issue has been addressed in the following products: Red Hat Enterprise Linux 7 Via RHSA-2020:1016 https://access.redhat.com/errata/RHSA-2020:1016
This issue has been addressed in the following products: Red Hat Enterprise Linux 7 Via RHSA-2020:1070 https://access.redhat.com/errata/RHSA-2020:1070