Security Vulnerabilities - CVEs Published In April 2020
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.
CVSS Score
7.8
EPSS Score
0.001
Published
2020-04-14
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.
CVSS Score
5.5
EPSS Score
0.001
Published
2020-04-14
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.
CVSS Score
8.8
EPSS Score
0.001
Published
2020-04-14
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.
CVSS Score
5.5
EPSS Score
0.0
Published
2020-04-14
An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service because of a bad error path in GNTTABOP_map_grant. Grant table operations are expected to return 0 for success, and a negative number for errors. Some misplaced brackets cause one error path to return 1 instead of a negative value. The grant table code in Linux treats this condition as success, and proceeds with incorrectly initialised state. A buggy or malicious guest can construct its grant table in such a way that, when a backend domain tries to map a grant, it hits the incorrect error path. This will crash a Linux based dom0 or backend domain.
CVSS Score
5.5
EPSS Score
0.0
Published
2020-04-14
The pc-kernel snap build process hardcoded the --allow-insecure-repositories and --allow-unauthenticated apt options when creating the build chroot environment. This could allow an attacker who is able to perform a MITM attack between the build environment and the Ubuntu archive to install a malicious package within the build chroot. This issue affects pc-kernel versions prior to and including 2019-07-16
CVSS Score
8.4
EPSS Score
0.004
Published
2020-04-14
CVE-2020-11738
The Snap Creek Duplicator plugin before 1.3.28 for WordPress (and Duplicator Pro before 3.8.7.1) allows Directory Traversal via ../ in the file parameter to duplicator_download or duplicator_init.
Known exploited
CVSS Score
7.5
EPSS Score
0.942
Published
2020-04-13
In Rockwell Automation RSLinx Classic versions 4.11.00 and prior, an authenticated local attacker could modify a registry key, which could lead to the execution of malicious code using system privileges when opening RSLinx Classic.
CVSS Score
7.8
EPSS Score
0.0
Published
2020-04-13
Fuji Electric V-Server Lite all versions prior to 4.0.9.0 contains a heap based buffer overflow. The buffer allocated to read data, when parsing VPR files, is too small.
CVSS Score
7.8
EPSS Score
0.002
Published
2020-04-13
fr-archive-libarchive.c in GNOME file-roller through 3.36.1 allows Directory Traversal during extraction because it lacks a check of whether a file's parent is a symlink to a directory outside of the intended extraction location.
CVSS Score
3.9
EPSS Score
0.001
Published
2020-04-13