Fedora Project Fedora 31

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.

In HylaFAX+ through 7.0.2 and HylaFAX Enterprise, the faxsetup utility calls chown on files in user-owned directories. By winning a race, a local attacker could use this to escalate his privileges to root.

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.

Insufficient policy enforcement in installer in Google Chrome on OS X prior to 85.0.4183.102 allowed a local attacker to potentially achieve privilege escalation via a crafted binary.

An issue was discovered in Xen through 4.14.x allowing x86 HVM and PVH guest OS users to cause a denial of service (data corruption), cause a data leak, or possibly gain privileges because coalescing of per-page IOMMU TLB flushes is mishandled.

Insufficient data validation in webUI in Google Chrome on ChromeOS prior to 86.0.4240.75 allowed a local attacker to bypass content security policy via a crafted HTML page.

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.

An issue was discovered in Xen through 4.13.x, allowing Intel guest OS users to gain privileges or cause a denial of service because of non-atomic modification of a live EPT PTE. When mapping guest EPT (nested paging) tables, Xen would in some circumstances use a series of non-atomic bitfield writes. Depending on the compiler version and optimisation flags, Xen might expose a dangerous partially written PTE to the hardware, which an attacker might be able to race to exploit. A guest administrator or perhaps even an unprivileged guest user might be able to cause denial of service, data corruption, or privilege escalation. Only systems using Intel CPUs are vulnerable. Systems using AMD CPUs, and Arm systems, are not vulnerable. Only systems using nested paging (hap, aka nested paging, aka in this case Intel EPT) are vulnerable. Only HVM and PVH guests can exploit the vulnerability. The presence and scope of the vulnerability depends on the precise optimisations performed by the compiler used to build Xen. If the compiler generates (a) a single 64-bit write, or (b) a series of read-modify-write operations in the same order as the source code, the hypervisor is not vulnerable. For example, in one test build using GCC 8.3 with normal settings, the compiler generated multiple (unlocked) read-modify-write operations in source-code order, which did not constitute a vulnerability. We have not been able to survey compilers; consequently we cannot say which compiler(s) might produce vulnerable code (with which code-generation options). The source code clearly violates the C rules, and thus should be considered vulnerable.

An issue was discovered in Xen through 4.14.x allowing x86 guest OS users to cause a denial of service (data corruption), cause a data leak, or possibly gain privileges because an AMD IOMMU page-table entry can be half-updated.

Insufficient policy enforcement in Intents in Google Chrome on Android prior to 86.0.4240.75 allowed a local attacker to bypass navigation restrictions via crafted Intents.

Inappropriate implementation in installer in Google Chrome on OS X prior to 83.0.4103.61 allowed a local attacker to perform privilege escalation via a crafted file.

Unauthorized File Access in npm CLI before before version 6.13.3

Arbitrary File Overwrite in npm CLI

A logic error in code which checks TSIG validity can be used to trigger an assertion failure in tsig.c

Apache HTTP Server versions 2.4.20 to 2.4.43. A specially crafted value for the 'Cache-Digest' header in a HTTP/2 request would result in a crash when the server actually tries to HTTP/2 PUSH a resource afterwards. Configuring the HTTP/2 feature via "H2Push off" will mitigate this vulnerability for unpatched servers.

An issue was discovered in Squid before 4.10. Due to incorrect buffer management, a remote client can cause a buffer overflow in a Squid instance acting as a reverse proxy.

Apache HTTP Server versions 2.4.20 to 2.4.43 When trace/debug was enabled for the HTTP/2 module and on certain traffic edge patterns, logging statements were made on the wrong connection, causing concurrent use of memory pools. Configuring the LogLevel of mod_http2 above "info" will mitigate this vulnerability for unpatched servers.

Segmentation fault in SSL_check_chain

ELOG 3.1.4-57bea22 and below is affected by an information disclosure vulnerability. A remote unauthenticated attacker can recover a user's password hash by sending a crafted HTTP POST request.

An issue was discovered in Squid 2.x, 3.x, and 4.x through 4.8. Due to incorrect data management, it is vulnerable to information disclosure when processing HTTP Digest Authentication. Nonce tokens contain the raw byte value of a pointer that sits within heap memory allocation. This information reduces ASLR protections and may aid attackers isolating memory areas to target for remote code execution attacks.

ELOG 3.1.4-57bea22 and below is affected by a denial of service vulnerability due to a NULL pointer dereference. A remote unauthenticated attacker can crash the ELOG server by sending a crafted HTTP GET request.

In Apache Commons Beanutils 1.9.2, a special BeanIntrospector class was added which allows suppressing the ability for an attacker to access the classloader via the class property available on all Java objects. We, however were not using this by default characteristic of the PropertyUtilsBean.

The Alias feature in SnakeYAML before 1.26 allows entity expansion during a load operation, a related issue to CVE-2003-1564.

The file name encoding algorithm used internally in Apache Commons Compress 1.15 to 1.18 can get into an infinite loop when faced with specially crafted inputs. This can lead to a denial of service attack if an attacker can choose the file names inside of an archive created by Compress.

An issue was discovered in Squid before 4.10. It allows a crafted FTP server to trigger disclosure of sensitive information from heap memory, such as information associated with other users' sessions or non-Squid processes.

An issue was discovered in Squid 3.x and 4.x through 4.8. Due to incorrect input validation, there is a heap-based buffer overflow that can result in Denial of Service to all clients using the proxy. Severity is high due to this vulnerability occurring before normal security checks; any remote client that can reach the proxy port can trivially perform the attack via a crafted URI scheme.

An issue was discovered in Squid before 4.10. Due to incorrect input validation, it can interpret crafted HTTP requests in unexpected ways to access server resources prohibited by earlier security filters.

cyrus-sasl (aka Cyrus SASL) 2.1.27 has an out-of-bounds write leading to unauthenticated remote denial-of-service in OpenLDAP via a malformed LDAP packet. The OpenLDAP crash is ultimately caused by an off-by-one error in _sasl_add_string in common.c in cyrus-sasl.

As mitigation for CVE-2020-1945 Apache Ant 1.10.8 changed the permissions of temporary files it created so that only the current user was allowed to access them. Unfortunately the fixcrlf task deleted the temporary file and created a new one without said protection, effectively nullifying the effort. This would still allow an attacker to inject modified source files into the build process.

xmlStringLenDecodeEntities in parser.c in libxml2 2.9.10 has an infinite loop in a certain end-of-file situation.

An issue was discovered in Pure-FTPd 1.0.49. An out-of-bounds (OOB) read has been detected in the pure_strcmp function in utils.c.

An issue was discovered in Oniguruma 6.x before 6.9.4_rc2. In the function fetch_interval_quantifier (formerly known as fetch_range_quantifier) in regparse.c, PFETCH is called without checking PEND. This leads to a heap-based buffer over-read.

The IEEE 802.11 parser in tcpdump before 4.9.3 has a buffer over-read in print-802_11.c for the Mesh Flags subfield.

The DCCP parser in tcpdump before 4.9.3 has a buffer over-read in print-dccp.c:dccp_print_option().

The JSON gem through 2.2.0 for Ruby, as used in Ruby 2.4 through 2.4.9, 2.5 through 2.5.7, and 2.6 through 2.6.5, has an Unsafe Object Creation Vulnerability. This is quite similar to CVE-2013-0269, but does not rely on poor garbage-collection behavior within Ruby. Specifically, use of JSON parsing methods can lead to creation of a malicious object within the interpreter, with adverse effects that are application-dependent.

A flaw in native PKCS#11 code can lead to a remotely triggerable assertion failure in pk11.c

In Lib/tarfile.py in Python through 3.8.3, an attacker is able to craft a TAR archive leading to an infinite loop when opened by tarfile.open, because _proc_pax lacks header validation.

In Dovecot before 2.3.11.3, sending a specially formatted RPA request will crash the auth service because a length of zero is mishandled.

In Dovecot before 2.3.11.3, sending a specially formatted NTLM request will crash the auth service because of an out-of-bounds read.

An exploitable denial-of-service vulnerability exists in the way CoTURN 4.5.1.1 web server parses POST requests. A specially crafted HTTP POST request can lead to server crash and denial of service. An attacker needs to send an HTTP request to trigger this vulnerability.