{
  "threat_severity" : "Moderate",
  "public_date" : "2017-10-09T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: Arbitrary stack overwrite causing oops via crafted signal frame",
    "id" : "1498067",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=1498067"
  },
  "cvss3" : {
    "cvss3_base_score" : "6.1",
    "cvss3_scoring_vector" : "CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-787",
  "details" : [ "On Linux running on PowerPC hardware (Power8 or later) a user process can craft a signal frame and then do a sigreturn so that the kernel will take an exception (interrupt), and use the r1 value *from the signal frame* as the kernel stack pointer. As part of the exception entry the content of the signal frame is written to the kernel stack, allowing an attacker to overwrite arbitrary locations with arbitrary values. The exception handling does produce an oops, and a panic if panic_on_oops=1, but only after kernel memory has been over written. This flaw was introduced in commit: \"5d176f751ee3 (powerpc: tm: Enable transactional memory (TM) lazily for userspace)\" which was merged upstream into v4.9-rc1. Please note that kernels built with CONFIG_PPC_TRANSACTIONAL_MEM=n are not vulnerable.", "A flaw was found in the Linux kernel's handling of signal frame on PowerPC systems. A malicious local user process could craft a signal frame allowing an attacker to corrupt memory." ],
  "statement" : "This issue does not affect the Linux kernel and kernel-rt packages as shipped with Red Hat Enterprise Linux 5, 6, and 7.",
  "acknowledgement" : "Red Hat would like to thank Breno Leitao, Cyril Bur, Gustavo Romero, Michael Ellerman, and Paul Mackerras for reporting this issue.",
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 7",
    "release_date" : "2018-04-10T00:00:00Z",
    "advisory" : "RHSA-2018:0654",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7",
    "package" : "kernel-alt-0:4.14.0-49.el7a"
  } ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 5",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:5"
  }, {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise MRG 2",
    "fix_state" : "Not affected",
    "package_name" : "realtime-kernel",
    "cpe" : "cpe:/a:redhat:enterprise_mrg:2"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2017-1000255\nhttps://nvd.nist.gov/vuln/detail/CVE-2017-1000255" ],
  "name" : "CVE-2017-1000255",
  "csaw" : false
}