CVE-2017-1000255

kernel: Arbitrary stack overwrite causing oops via crafted signal frame

Published Oct 30, 2017 CVSS 3.0 · 5.5 Medium EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
EUVD EUVD EUVD-2017-1516 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.
Ubuntu USN Ubuntu USN USN-3443-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-3443-2 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-3487-1 Linux kernel vulnerabilities
History

No history.

Weaknesses

Sources

Status
PUBLISHED
Assigner
mitre
Published
Updated
Aug 5, 2024, 10:00 PM
Reserved
Oct 6, 2017, 12:00 AM
Status
Modified
Published
Oct 30, 2017, 8:29 PM
Modified
Jun 17, 2026, 12:59 AM
Severity
Moderate
Public date
Oct 9, 2017, 12:00 AM