The xen_biovec_phys_mergeable function in drivers/xen/biomerge.c in Xen might allow local OS guest users to corrupt block device data strea…

published 2017-08-24 9 y ago modified 2026-06-17 4 mo ago also EUVD-2017-3718

cvss: 8.8; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 42%
public exploits: 0; none known

The xen_biovec_phys_mergeable function in drivers/xen/biomerge.c in Xen might allow local OS guest users to corrupt block device data streams and consequently obtain sensitive memory information, cause a denial of service, or gain host OS privileges by leveraging incorrect block IO merge-ability calculation.

Patch / fix

distros 3 links 3

debian ubuntu suse

linux Debian 14, Debian 13, Debian 12 4.12.12-1

debian advisories DEBIAN-CVE-2017-12134

linux Ubuntu 14.04 LTS 3.13.0-149.199
linux Ubuntu 16.04 LTS 4.4.0-97.120
linux-aws Ubuntu 16.04 LTS 4.4.0-1038.47
linux-gcp Ubuntu 16.04 LTS 4.13.0-1002.5
linux-gke Ubuntu 16.04 LTS 4.4.0-1032.32
linux-hwe Ubuntu 16.04 LTS 4.13.0-32.35~16.04.1
linux-kvm Ubuntu 16.04 LTS 4.4.0-1008.13
linux-azure Ubuntu 16.04 LTS 4.13.0-1005.7

ubuntu advisories UBUNTU-CVE-2017-12134

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

kernel-rt SLE Real Time 12 SP2 4.4.88-18.1
kernel-syms-rt SLE Real Time 12 SP2 4.4.88-18.1
kernel-rt_debug SLE Real Time 12 SP2 4.4.88-18.1
kernel-source-rt SLE Real Time 12 SP2 4.4.88-18.1
kernel-syms SLES for SAP 12 SP2, SLES for Raspberry Pi 12 SP2, SLES 12 SP2 +1 more 4.4.90-92.45.1
kernel-source SLES for SAP 12 SP2, SLES for Raspberry Pi 12 SP2, SLES 12 SP2 +1 more 4.4.90-92.45.1
kernel-default SLES for SAP 12 SP2, SLES for Raspberry Pi 12 SP2, SLES 12 SP2 +3 more 4.4.90-92.45.1
kernel-obs-build SLE Software Development Kit 12 SP2 4.4.90-92.45.1

suse advisories SUSE-SU-2017:2956-1 SUSE-SU-2017:2869-1 SUSE-SU-2017:2847-1

support.citrix.com/article/CTX225941 advisory
xenbits.xen.org/xsa/advisory-229.html advisory
bugzilla.redhat.com/show_bug.cgi?id=1477656 advisory

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2017-12134 updated 2026-11-05 cvss 7.5

xen: linux: Fix Xen block IO merge-ability calculation (XSA-229)

Red Hat Enterprise Linux 5 xen
affected: no fix planned “Will not fix”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.50% chance of exploitation in the next 30 days, higher than 42% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
NVD	3.0	8.8	CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
NVD	2.0	7.2	AV:L/AC:L/Au:N/C:C/I:C/A:C

Classification

Weakness

CWE-682 Incorrect Calculation

References

support.citrix.com /article/CTX225941
patch, third-party-advisory
xenbits.xen.org /xsa/advisory-229.html
mitigation, patch, vendor-advisory
bugzilla.redhat.com /show_bug.cgi?id=1477656
issue-tracking, mitigation, patch, third-party-advisory
debian.org /security/2017/dsa-3981
vendor-advisory
usn.ubuntu.com /3655-1/
vendor-advisory
security.gentoo.org /glsa/201801-14
vendor-advisory
usn.ubuntu.com /3655-2/
vendor-advisory
securitytracker.com /id/1039176
vdb-entry, third-party-advisory
openwall.com /lists/oss-security/2017/08/15/4
mailing-list, mitigation, third-party-advisory
securityfocus.com /bid/100343
vdb-entry, third-party-advisory

Sources

CVE List CVE-2017-12134
NVD CVE-2017-12134

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary