Vulnerabilities (CVE)

Filtered by vendor Fedoraproject Subscribe
Total 5187 CVE
CVE Vendors Products Updated CVSS v2 CVSS v3
CVE-2020-25603 4 Debian, Fedoraproject, Opensuse and 1 more 4 Debian Linux, Fedora, Leap and 1 more 2024-11-21 4.6 MEDIUM 7.8 HIGH
An issue was discovered in Xen through 4.14.x. There are missing memory barriers when accessing/allocating an event channel. Event channels control structures can be accessed lockless as long as the port is considered to be valid. Such a sequence is missing an appropriate memory barrier (e.g., smp_*mb()) to prevent both the compiler and CPU from re-ordering access. A malicious guest may be able to cause a hypervisor crash resulting in a Denial of Service (DoS). Information leak and privilege escalation cannot be excluded. Systems running all versions of Xen are affected. Whether a system is vulnerable will depend on the CPU and compiler used to build Xen. For all systems, the presence and the scope of the vulnerability depend on the precise re-ordering performed by the compiler used to build Xen. We have not been able to survey compilers; consequently we cannot say which compiler(s) might produce vulnerable code (with which code generation options). GCC documentation clearly suggests that re-ordering is possible. Arm systems will also be vulnerable if the CPU is able to re-order memory access. Please consult your CPU vendor. x86 systems are only vulnerable if a compiler performs re-ordering.
CVE-2020-25602 4 Debian, Fedoraproject, Opensuse and 1 more 4 Debian Linux, Fedora, Leap and 1 more 2024-11-21 4.6 MEDIUM 6.0 MEDIUM
An issue was discovered in Xen through 4.14.x. An x86 PV guest can trigger a host OS crash when handling guest access to MSR_MISC_ENABLE. When a guest accesses certain Model Specific Registers, Xen first reads the value from hardware to use as the basis for auditing the guest access. For the MISC_ENABLE MSR, which is an Intel specific MSR, this MSR read is performed without error handling for a #GP fault, which is the consequence of trying to read this MSR on non-Intel hardware. A buggy or malicious PV guest administrator can crash Xen, resulting in a host Denial of Service. Only x86 systems are vulnerable. ARM systems are not vulnerable. Only Xen versions 4.11 and onwards are vulnerable. 4.10 and earlier are not vulnerable. Only x86 systems that do not implement the MISC_ENABLE MSR (0x1a0) are vulnerable. AMD and Hygon systems do not implement this MSR and are vulnerable. Intel systems do implement this MSR and are not vulnerable. Other manufacturers have not been checked. Only x86 PV guests can exploit the vulnerability. x86 HVM/PVH guests cannot exploit the vulnerability.
CVE-2020-25601 4 Debian, Fedoraproject, Opensuse and 1 more 4 Debian Linux, Fedora, Leap and 1 more 2024-11-21 4.9 MEDIUM 5.5 MEDIUM
An issue was discovered in Xen through 4.14.x. There is a lack of preemption in evtchn_reset() / evtchn_destroy(). In particular, the FIFO event channel model allows guests to have a large number of event channels active at a time. Closing all of these (when resetting all event channels or when cleaning up after the guest) may take extended periods of time. So far, there was no arrangement for preemption at suitable intervals, allowing a CPU to spend an almost unbounded amount of time in the processing of these operations. Malicious or buggy guest kernels can mount a Denial of Service (DoS) attack affecting the entire system. All Xen versions are vulnerable in principle. Whether versions 4.3 and older are vulnerable depends on underlying hardware characteristics.
CVE-2020-25600 4 Debian, Fedoraproject, Opensuse and 1 more 4 Debian Linux, Fedora, Leap and 1 more 2024-11-21 4.9 MEDIUM 5.5 MEDIUM
An issue was discovered in Xen through 4.14.x. Out of bounds event channels are available to 32-bit x86 domains. The so called 2-level event channel model imposes different limits on the number of usable event channels for 32-bit x86 domains vs 64-bit or Arm (either bitness) ones. 32-bit x86 domains can use only 1023 channels, due to limited space in their shared (between guest and Xen) information structure, whereas all other domains can use up to 4095 in this model. The recording of the respective limit during domain initialization, however, has occurred at a time where domains are still deemed to be 64-bit ones, prior to actually honoring respective domain properties. At the point domains get recognized as 32-bit ones, the limit didn't get updated accordingly. Due to this misbehavior in Xen, 32-bit domains (including Domain 0) servicing other domains may observe event channel allocations to succeed when they should really fail. Subsequent use of such event channels would then possibly lead to corruption of other parts of the shared info structure. An unprivileged guest may cause another domain, in particular Domain 0, to misbehave. This may lead to a Denial of Service (DoS) for the entire system. All Xen versions from 4.4 onwards are vulnerable. Xen versions 4.3 and earlier are not vulnerable. Only x86 32-bit domains servicing other domains are vulnerable. Arm systems, as well as x86 64-bit domains, are not vulnerable.
CVE-2020-25599 4 Debian, Fedoraproject, Opensuse and 1 more 4 Debian Linux, Fedora, Leap and 1 more 2024-11-21 4.4 MEDIUM 7.0 HIGH
An issue was discovered in Xen through 4.14.x. There are evtchn_reset() race conditions. Uses of EVTCHNOP_reset (potentially by a guest on itself) or XEN_DOMCTL_soft_reset (by itself covered by XSA-77) can lead to the violation of various internal assumptions. This may lead to out of bounds memory accesses or triggering of bug checks. In particular, x86 PV guests may be able to elevate their privilege to that of the host. Host and guest crashes are also possible, leading to a Denial of Service (DoS). Information leaks cannot be ruled out. All Xen versions from 4.5 onwards are vulnerable. Xen versions 4.4 and earlier are not vulnerable.
CVE-2020-25598 3 Fedoraproject, Opensuse, Xen 3 Fedora, Leap, Xen 2024-11-21 2.1 LOW 5.5 MEDIUM
An issue was discovered in Xen 4.14.x. There is a missing unlock in the XENMEM_acquire_resource error path. The RCU (Read, Copy, Update) mechanism is a synchronisation primitive. A buggy error path in the XENMEM_acquire_resource exits without releasing an RCU reference, which is conceptually similar to forgetting to unlock a spinlock. A buggy or malicious HVM stubdomain can cause an RCU reference to be leaked. This causes subsequent administration operations, (e.g., CPU offline) to livelock, resulting in a host Denial of Service. The buggy codepath has been present since Xen 4.12. Xen 4.14 and later are vulnerable to the DoS. The side effects are believed to be benign on Xen 4.12 and 4.13, but patches are provided nevertheless. The vulnerability can generally only be exploited by x86 HVM VMs, as these are generally the only type of VM that have a Qemu stubdomain. x86 PV and PVH domains, as well as ARM VMs, typically don't use a stubdomain. Only VMs using HVM stubdomains can exploit the vulnerability. VMs using PV stubdomains, or with emulators running in dom0, cannot exploit the vulnerability.
CVE-2020-25597 2 Fedoraproject, Xen 2 Fedora, Xen 2024-11-21 6.1 MEDIUM 6.5 MEDIUM
An issue was discovered in Xen through 4.14.x. There is mishandling of the constraint that once-valid event channels may not turn invalid. Logic in the handling of event channel operations in Xen assumes that an event channel, once valid, will not become invalid over the life time of a guest. However, operations like the resetting of all event channels may involve decreasing one of the bounds checked when determining validity. This may lead to bug checks triggering, crashing the host. An unprivileged guest may be able to crash Xen, leading to a Denial of Service (DoS) for the entire system. All Xen versions from 4.4 onwards are vulnerable. Xen versions 4.3 and earlier are not vulnerable. Only systems with untrusted guests permitted to create more than the default number of event channels are vulnerable. This number depends on the architecture and type of guest. For 32-bit x86 PV guests, this is 1023; for 64-bit x86 PV guests, and for all ARM guests, this number is 4095. Systems where untrusted guests are limited to fewer than this number are not vulnerable. Note that xl and libxl limit max_event_channels to 1023 by default, so systems using exclusively xl, libvirt+libxl, or their own toolstack based on libxl, and not explicitly setting max_event_channels, are not vulnerable.
CVE-2020-25596 4 Debian, Fedoraproject, Opensuse and 1 more 4 Debian Linux, Fedora, Leap and 1 more 2024-11-21 2.1 LOW 5.5 MEDIUM
An issue was discovered in Xen through 4.14.x. x86 PV guest kernels can experience denial of service via SYSENTER. The SYSENTER instruction leaves various state sanitization activities to software. One of Xen's sanitization paths injects a #GP fault, and incorrectly delivers it twice to the guest. This causes the guest kernel to observe a kernel-privilege #GP fault (typically fatal) rather than a user-privilege #GP fault (usually converted into SIGSEGV/etc.). Malicious or buggy userspace can crash the guest kernel, resulting in a VM Denial of Service. All versions of Xen from 3.2 onwards are vulnerable. Only x86 systems are vulnerable. ARM platforms are not vulnerable. Only x86 systems that support the SYSENTER instruction in 64bit mode are vulnerable. This is believed to be Intel, Centaur, and Shanghai CPUs. AMD and Hygon CPUs are not believed to be vulnerable. Only x86 PV guests can exploit the vulnerability. x86 PVH / HVM guests cannot exploit the vulnerability.
CVE-2020-25595 4 Debian, Fedoraproject, Opensuse and 1 more 4 Debian Linux, Fedora, Leap and 1 more 2024-11-21 6.1 MEDIUM 7.8 HIGH
An issue was discovered in Xen through 4.14.x. The PCI passthrough code improperly uses register data. Code paths in Xen's MSI handling have been identified that act on unsanitized values read back from device hardware registers. While devices strictly compliant with PCI specifications shouldn't be able to affect these registers, experience shows that it's very common for devices to have out-of-spec "backdoor" operations that can affect the result of these reads. A not fully trusted guest may be able to crash Xen, leading to a Denial of Service (DoS) for the entire system. Privilege escalation and information leaks cannot be excluded. All versions of Xen supporting PCI passthrough are affected. Only x86 systems are vulnerable. Arm systems are not vulnerable. Only guests with passed through PCI devices may be able to leverage the vulnerability. Only systems passing through devices with out-of-spec ("backdoor") functionality can cause issues. Experience shows that such out-of-spec functionality is common; unless you have reason to believe that your device does not have such functionality, it's better to assume that it does.
CVE-2020-25275 3 Debian, Dovecot, Fedoraproject 3 Debian Linux, Dovecot, Fedora 2024-11-21 5.0 MEDIUM 7.5 HIGH
Dovecot before 2.3.13 has Improper Input Validation in lda, lmtp, and imap, leading to an application crash via a crafted email message with certain choices for ten thousand MIME parts.
CVE-2020-25219 5 Canonical, Debian, Fedoraproject and 2 more 5 Ubuntu Linux, Debian Linux, Fedora and 2 more 2024-11-21 5.0 MEDIUM 7.5 HIGH
url::recvline in url.cpp in libproxy 0.4.x through 0.4.15 allows a remote HTTP server to trigger uncontrolled recursion via a response composed of an infinite stream that lacks a newline character. This leads to stack exhaustion.
CVE-2020-25211 3 Debian, Fedoraproject, Linux 3 Debian Linux, Fedora, Linux Kernel 2024-11-21 3.6 LOW 6.0 MEDIUM
In the Linux kernel through 5.8.7, local attackers able to inject conntrack netlink configuration could overflow a local buffer, causing crashes or triggering use of incorrect protocol numbers in ctnetlink_parse_tuple_filter in net/netfilter/nf_conntrack_netlink.c, aka CID-1cc5ef91d2ff.
CVE-2020-25097 4 Debian, Fedoraproject, Netapp and 1 more 4 Debian Linux, Fedora, Cloud Manager and 1 more 2024-11-21 5.0 MEDIUM 8.6 HIGH
An issue was discovered in Squid through 4.13 and 5.x through 5.0.4. Due to improper input validation, it allows a trusted client to perform HTTP Request Smuggling and access services otherwise forbidden by the security controls. This occurs for certain uri_whitespace configuration settings.
CVE-2020-24977 6 Debian, Fedoraproject, Netapp and 3 more 19 Debian Linux, Fedora, Active Iq Unified Manager and 16 more 2024-11-21 6.4 MEDIUM 6.5 MEDIUM
GNOME project libxml2 v2.9.10 has a global buffer over-read vulnerability in xmlEncodeEntitiesInternal at libxml2/entities.c. The issue has been fixed in commit 50f06b3e.
CVE-2020-24972 3 Fedoraproject, Kleopatra Project, Opensuse 4 Fedora, Kleopatra, Backports Sle and 1 more 2024-11-21 6.5 MEDIUM 8.8 HIGH
The Kleopatra component before 3.1.12 (and before 20.07.80) for GnuPG allows remote attackers to execute arbitrary code because openpgp4fpr: URLs are supported without safe handling of command-line options. The Qt platformpluginpath command-line option can be used to load an arbitrary DLL.
CVE-2020-24661 2 Fedoraproject, Gnome 2 Fedora, Geary 2024-11-21 2.6 LOW 5.9 MEDIUM
GNOME Geary before 3.36.3 mishandles pinned TLS certificate verification for IMAP and SMTP services using invalid TLS certificates (e.g., self-signed certificates) when the client system is not configured to use a system-provided PKCS#11 store. This allows a meddler in the middle to present a different invalid certificate to intercept incoming and outgoing mail.
CVE-2020-24659 4 Canonical, Fedoraproject, Gnu and 1 more 4 Ubuntu Linux, Fedora, Gnutls and 1 more 2024-11-21 5.0 MEDIUM 7.5 HIGH
An issue was discovered in GnuTLS before 3.6.15. A server can trigger a NULL pointer dereference in a TLS 1.3 client if a no_renegotiation alert is sent with unexpected timing, and then an invalid second handshake occurs. The crash happens in the application's error handling path, where the gnutls_deinit function is called after detecting a handshake failure.
CVE-2020-24654 5 Canonical, Debian, Fedoraproject and 2 more 5 Ubuntu Linux, Debian Linux, Fedora and 2 more 2024-11-21 4.3 MEDIUM 3.3 LOW
In KDE Ark before 20.08.1, a crafted TAR archive with symlinks can install files outside the extraction directory, as demonstrated by a write operation to a user's home directory.
CVE-2020-24614 3 Fedoraproject, Fossil-scm, Opensuse 4 Fedora, Fossil, Backports Sle and 1 more 2024-11-21 6.5 MEDIUM 8.8 HIGH
Fossil before 2.10.2, 2.11.x before 2.11.2, and 2.12.x before 2.12.1 allows remote authenticated users to execute arbitrary code. An attacker must have check-in privileges on the repository.
CVE-2020-24612 1 Fedoraproject 1 Selinux-policy 2024-11-21 1.9 LOW 6.7 MEDIUM
An issue was discovered in the selinux-policy (aka Reference Policy) package 3.14 through 2020-08-24 because the .config/Yubico directory is mishandled. Consequently, when SELinux is in enforced mode, pam-u2f is not allowed to read the user's U2F configuration file. If configured with the nouserok option (the default when configured by the authselect tool), and that file cannot be read, the second factor is disabled. An attacker with only the knowledge of the password can then log in, bypassing 2FA.