Описание
Security update for xen
This update for xen fixes the following issues:
- bsc#1174543 - secure boot related fixes
- bsc#1163019 - CVE-2020-8608: Potential OOB access due to unsafe snprintf() usages
- bsc#1169392 - CVE-2020-11742: Bad continuation handling in GNTTABOP_copy
- bsc#1168140 - CVE-2020-11740, CVE-2020-11741: Multiple xenoprof issues
- bsc#1168142 - CVE-2020-11739: Missing memory barriers in read-write unlock paths
Список пакетов
SUSE Linux Enterprise Server 12 SP2-BCL
SUSE Linux Enterprise Server 12 SP2-LTSS
SUSE Linux Enterprise Server for SAP Applications 12 SP2
SUSE OpenStack Cloud 7
Ссылки
- Link for SUSE-SU-2020:2234-1
- E-Mail link for SUSE-SU-2020:2234-1
- SUSE Security Ratings
- SUSE Bug 1163019
- SUSE Bug 1168140
- SUSE Bug 1168142
- SUSE Bug 1169392
- SUSE Bug 1174543
- SUSE CVE CVE-2020-11739 page
- SUSE CVE CVE-2020-11740 page
- SUSE CVE CVE-2020-11741 page
- SUSE CVE CVE-2020-11742 page
- SUSE CVE CVE-2020-8608 page
Описание
An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service or possibly gain privileges because of missing memory barriers in read-write unlock paths. The read-write unlock paths don't contain a memory barrier. On Arm, this means a processor is allowed to re-order the memory access with the preceding ones. In other words, the unlock may be seen by another processor before all the memory accesses within the "critical" section. As a consequence, it may be possible to have a writer executing a critical section at the same time as readers or another writer. In other words, many of the assumptions (e.g., a variable cannot be modified after a check) in the critical sections are not safe anymore. The read-write locks are used in hypercalls (such as grant-table ones), so a malicious guest could exploit the race. For instance, there is a small window where Xen can leak memory if XENMAPSPACE_grant_table is used concurrently. A malicious guest may be able to leak memory, or cause a hypervisor crash resulting in a Denial of Service (DoS). Information leak and privilege escalation cannot be excluded.
Затронутые продукты
Ссылки
- CVE-2020-11739
- SUSE Bug 1168142
Описание
An issue was discovered in xenoprof in Xen through 4.13.x, allowing guest OS users (without active profiling) to obtain sensitive information about other guests. Unprivileged guests can request to map xenoprof buffers, even if profiling has not been enabled for those guests. These buffers were not scrubbed.
Затронутые продукты
Ссылки
- CVE-2020-11740
- SUSE Bug 1168140
- SUSE Bug 1178658
Описание
An issue was discovered in xenoprof in Xen through 4.13.x, allowing guest OS users (with active profiling) to obtain sensitive information about other guests, cause a denial of service, or possibly gain privileges. For guests for which "active" profiling was enabled by the administrator, the xenoprof code uses the standard Xen shared ring structure. Unfortunately, this code did not treat the guest as a potential adversary: it trusts the guest not to modify buffer size information or modify head / tail pointers in unexpected ways. This can crash the host (DoS). Privilege escalation cannot be ruled out.
Затронутые продукты
Ссылки
- CVE-2020-11741
- SUSE Bug 1168140
- SUSE Bug 1178658
Описание
An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service because of bad continuation handling in GNTTABOP_copy. Grant table operations are expected to return 0 for success, and a negative number for errors. The fix for CVE-2017-12135 introduced a path through grant copy handling where success may be returned to the caller without any action taken. In particular, the status fields of individual operations are left uninitialised, and may result in errant behaviour in the caller of GNTTABOP_copy. A buggy or malicious guest can construct its grant table in such a way that, when a backend domain tries to copy a grant, it hits the incorrect exit path. This returns success to the caller without doing anything, which may cause crashes or other incorrect behaviour.
Затронутые продукты
Ссылки
- CVE-2020-11742
- SUSE Bug 1169392
- SUSE Bug 1178658
Описание
In libslirp 4.1.0, as used in QEMU 4.2.0, tcp_subr.c misuses snprintf return values, leading to a buffer overflow in later code.
Затронутые продукты
Ссылки
- CVE-2020-8608
- SUSE Bug 1163018
- SUSE Bug 1163019