DEBIAN-CVE-2017-1000255

Advisory lineage Upstream: 1 Downstream: 0
Published: 30 Oct 2017, 20:29
Last modified:28 Apr 2026, 20:16

Vulnerability Summary

Overall Risk (default)
low
22/100
CVSS Score
5.5 MEDIUM
3.0 (osv_debian)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

30 Oct 2017, 20:29
Published
Vulnerability first disclosed
28 Apr 2026, 20:16
Last Modified
Vulnerability information updated

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.

CVSS Metrics

  • v3.0•MEDIUM•Score: 5.5CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

Affected Systems

  • debian•linux

    < 4.13.4-2 | < 4.13.4-2 | < 4.13.4-2 | < 4.13.4-2

References (1)