CVE-2018-8897

Priority
Description
A statement in the System Programming Guide of the Intel 64 and IA-32
Architectures Software Developer's Manual (SDM) was mishandled in the
development of some or all operating-system kernels, resulting in
unexpected behavior for #DB exceptions that are deferred by MOV SS or POP
SS, as demonstrated by (for example) privilege escalation in Windows,
macOS, some Xen configurations, or FreeBSD, or a Linux kernel crash. The
MOV to SS and POP SS instructions inhibit interrupts (including NMIs), data
breakpoints, and single step trap exceptions until the instruction boundary
following the next instruction (SDM Vol. 3A; section 6.8.3). (The inhibited
data breakpoints are those on memory accessed by the MOV to SS or POP to SS
instruction itself.) Note that debug exceptions are not inhibited by the
interrupt enable (EFLAGS.IF) system flag (SDM Vol. 3A; section 2.3). If the
instruction following the MOV to SS or POP to SS instruction is an
instruction like SYSCALL, SYSENTER, INT 3, etc. that transfers control to
the operating system at CPL < 3, the debug exception is delivered after the
transfer to CPL < 3 is complete. OS kernels may not expect this order of
events and may therefore experience unexpected behavior when it occurs.
Ubuntu-Description
Nick Peterson discovered that the Linux kernel did not properly handle
debug exceptions following a MOV/POP to SS instruction. A local attacker
could use this to cause a denial of service (system crash). This issue only
affected the amd64 architecture.
Notes
tyhicksThanks to Andy Lutomirski for help in Linux kernel research and test
case
Package
Source: linux (LP Ubuntu Debian)
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):released (3.2.0-134.180)
Ubuntu 14.04 ESM (Trusty Tahr):released (3.13.0-147.196)
Ubuntu 16.04 LTS (Xenial Xerus):released (4.4.0-124.148)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (landed pre-release in 4.15.0-15.16)
Patches:
Break-fix:-
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):released (4.4.0-1019.19)
Ubuntu 16.04 LTS (Xenial Xerus):released (4.4.0-1057.66)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (4.15.0-1003.3)
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):not-affected (4.15.0-1023.24~14.04.1)
Ubuntu 16.04 LTS (Xenial Xerus):released (4.13.0-1016.19)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (4.15.0-1004.4)
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):released (4.4.0-9027.29)
Ubuntu 18.04 LTS (Bionic Beaver):DNE
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE (trusty was ignored [abandoned])
Ubuntu 16.04 LTS (Xenial Xerus):ignored (abandoned)
Ubuntu 18.04 LTS (Bionic Beaver):DNE
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):released (4.13.0-1015.19)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (4.15.0-1003.3)
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):ignored (was needs-triage now end-of-life)
Ubuntu 18.04 LTS (Bionic Beaver):DNE
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE (trusty was ignored [abandoned])
Ubuntu 16.04 LTS (Xenial Xerus):ignored (was needs-triage now end-of-life)
Ubuntu 18.04 LTS (Bionic Beaver):DNE
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE (trusty was ignored [abandoned])
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):DNE
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):released (4.13.0-41.46~16.04.1)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):released (4.13.0-41.46~16.04.1)
Ubuntu 18.04 LTS (Bionic Beaver):released (4.18.0-8.9~18.04.1)
Product
linux-krillin:not-affected (x86 only)
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):released (4.4.0-1023.28)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (4.15.0-1004.4)
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):released (3.13.0-147.196~precise1)
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):DNE
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE (trusty was ignored [out of standard support])
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):DNE
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE (trusty was ignored [out of standard support])
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):DNE
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE (trusty was ignored [out of standard support])
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):DNE
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):released (4.4.0-124.148~14.04.1)
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):DNE
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE (trusty was ignored [abandoned])
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):DNE
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE (trusty was ignored [abandoned])
Ubuntu 16.04 LTS (Xenial Xerus):ignored (abandoned)
Ubuntu 18.04 LTS (Bionic Beaver):DNE
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE (trusty was ignored [abandoned])
Ubuntu 16.04 LTS (Xenial Xerus):DNE
Ubuntu 18.04 LTS (Bionic Beaver):DNE
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):released (4.13.0-1026.29)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (4.15.0-1002.3)
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):not-affected (x86 only)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (x86 only)
Package
Upstream:released (4.16~rc7)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):DNE
Ubuntu 16.04 LTS (Xenial Xerus):not-affected (x86 only)
Ubuntu 18.04 LTS (Bionic Beaver):not-affected
Product
linux-vegetahd:not-affected (x86 only)
More Information

Updated: 2020-09-10 06:03:32 UTC (commit 81a23a978c4436cd99e1d040e9e73e9146876281)