Redhat » Enterprise Linux : Security Vulnerabilities, CVEs, (Denial of service) CVSS score >= 6

A double free vulnerability was found in QEMU virtio devices (virtio-gpu, virtio-serial-bus, virtio-crypto), where the mem_reentrancy_guard flag insufficiently protects against DMA reentrancy issues. This issue could allow a malicious privileged guest user to crash the QEMU process on the host, resulting in a denial of service or allow arbitrary code execution within the context of the QEMU process on the host.

A flaw was found in the RPC library APIs of libvirt. The RPC server deserialization code allocates memory for arrays before the non-negative length check is performed by the C API entry points. Passing a negative length to the g_new0 function results in a crash due to the negative length being treated as a huge positive number. This flaw allows a local, unprivileged user to perform a denial of service attack by causing the libvirt daemon to crash.

A flaw was found in the Open Virtual Network (OVN). In OVN clusters where BFD is used between hypervisors for high availability, an attacker can inject specially crafted BFD packets from inside unprivileged workloads, including virtual machines or containers, that can trigger a denial of service.

A flaw was found in the Netfilter subsystem in the Linux kernel. The issue is in the nft_byteorder_eval() function, where the code iterates through a loop and writes to the `dst` array. On each iteration, 8 bytes are written, but `dst` is an array of u32, so each element only has space for 4 bytes. That means every iteration overwrites part of the previous element corrupting this array of u32. This flaw allows a local user to cause a denial of service or potentially break NetFilter functionality.

A segment fault (SEGV) flaw was found in libtiff that could be triggered by passing a crafted tiff file to the TIFFReadRGBATileExt() API. This flaw allows a remote attacker to cause a heap-buffer overflow, leading to a denial of service.

An out-of-memory flaw was found in libtiff that could be triggered by passing a crafted tiff file to the TIFFRasterScanlineSize64() API. This flaw allows a remote attacker to cause a denial of service via a crafted input with a size smaller than 379 KB.

Certain DNSSEC aspects of the DNS protocol (in RFC 4033, 4034, 4035, 6840, and related RFCs) allow remote attackers to cause a denial of service (CPU consumption) via one or more DNSSEC responses, aka the "KeyTrap" issue. One of the concerns is that, when there is a zone with many DNSKEY and RRSIG records, the protocol specification implies that an algorithm must evaluate all combinations of DNSKEY and RRSIG records.

Squid is vulnerable to Denial of Service, where a remote attacker can perform DoS by sending ftp:// URLs in HTTP Request messages or constructing ftp:// URLs from FTP Native input.

Squid is vulnerable to a Denial of Service, where a remote attacker can perform buffer overflow attack by writing up to 2 MB of arbitrary data to heap memory when Squid is configured to accept HTTP Digest Authentication.

The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation can reset many streams quickly, as exploited in the wild in August through October 2023.

A flaw was found in the IPv4 Resource Reservation Protocol (RSVP) classifier in the Linux kernel. The xprt pointer may go beyond the linear part of the skb, leading to an out-of-bounds read in the `rsvp_classify` function. This issue may allow a local user to crash the system and cause a denial of service.

A vulnerability was found in Samba's "rpcecho" development server, a non-Windows RPC server used to test Samba's DCE/RPC stack elements. This vulnerability stems from an RPC function that can be blocked indefinitely. The issue arises because the "rpcecho" service operates with only one worker in the main RPC task, allowing calls to the "rpcecho" server to be blocked for a specified time, causing service disruptions. This disruption is triggered by a "sleep()" call in the "dcesrv_echo_TestSleep()" function under specific conditions. Authenticated users or attackers can exploit this vulnerability to make calls to the "rpcecho" server, requesting it to block for a specified duration, effectively disrupting most services and leading to a complete denial of service on the AD DC. The DoS affects all other services as "rpcecho" runs in the main RPC task.

A vulnerability was found in libtiff due to multiple potential integer overflows in raw2tiff.c. This flaw allows remote attackers to cause a denial of service or possibly execute an arbitrary code via a crafted tiff image, which triggers a heap-based buffer overflow.

LibTIFF is vulnerable to an integer overflow. This flaw allows remote attackers to cause a denial of service (application crash) or possibly execute an arbitrary code via a crafted tiff image, which triggers a heap-based buffer overflow.

An out-of-bounds read flaw was found in Shim due to the lack of proper boundary verification during the load of a PE binary. This flaw allows an attacker to load a crafted PE binary, triggering the issue and crashing Shim, resulting in a denial of service.

A race condition was found in the QXL driver in the Linux kernel. The qxl_mode_dumb_create() function dereferences the qobj returned by the qxl_gem_object_create_with_handle(), but the handle is the only one holding a reference to it. This flaw allows an attacker to guess the returned handle value and trigger a use-after-free issue, potentially leading to a denial of service or privilege escalation.

A flaw was found in Keylime. Due to their blocking nature, the Keylime registrar is subject to a remote denial of service against its SSL connections. This flaw allows an attacker to exhaust all available connections.

An infinite loop vulnerability was found in Samba's mdssvc RPC service for Spotlight. When parsing Spotlight mdssvc RPC packets sent by the client, the core unmarshalling function sl_unpack_loop() did not validate a field in the network packet that contains the count of elements in an array-like structure. By passing 0 as the count value, the attacked function will run in an endless loop consuming 100% CPU. This flaw allows an attacker to issue a malformed RPC request, triggering an infinite loop, resulting in a denial of service condition.

A heap buffer overflow vulnerability was found in sox, in the lsx_readbuf function at sox/src/formats_i.c:98:16. This flaw can lead to a denial of service, code execution, or information disclosure.

A heap buffer overflow vulnerability was found in sox, in the startread function at sox/src/hcom.c:160:41. This flaw can lead to a denial of service, code execution, or information disclosure.

A floating point exception vulnerability was found in sox, in the read_samples function at sox/src/voc.c:334:18. This flaw can lead to a denial of service.

Apptainer is an open source container platform for Linux. There is an ext4 use-after-free flaw that is exploitable through versions of Apptainer < 1.1.0 and installations that include apptainer-suid < 1.1.8 on older operating systems where that CVE has not been patched. That includes Red Hat Enterprise Linux 7, Debian 10 buster (unless the linux-5.10 package is installed), Ubuntu 18.04 bionic and Ubuntu 20.04 focal. Use-after-free flaws in the kernel can be used to attack the kernel for denial of service and potentially for privilege escalation. Apptainer 1.1.8 includes a patch that by default disables mounting of extfs filesystem types in setuid-root mode, while continuing to allow mounting of extfs filesystems in non-setuid "rootless" mode using fuse2fs. Some workarounds are possible. Either do not install apptainer-suid (for versions 1.1.0 through 1.1.7) or set `allow setuid = no` in apptainer.conf. This requires having unprivileged user namespaces enabled and except for apptainer 1.1.x versions will disallow mounting of sif files, extfs files, and squashfs files in addition to other, less significant impacts. (Encrypted sif files are also not supported unprivileged in apptainer 1.1.x.). Alternatively, use the `limit containers` options in apptainer.conf/singularity.conf to limit sif files to trusted users, groups, and/or paths, and set `allow container extfs = no` to disallow mounting of extfs overlay files. The latter option by itself does not disallow mounting of extfs overlay partitions inside SIF files, so that's why the former options are also needed.

A floating point exception vulnerability was found in sox, in the lsx_aiffstartwrite function at sox/src/aiff.c:622:58. This flaw can lead to a denial of service.

A Null pointer dereference problem was found in ida_free in lib/idr.c in the Linux Kernel. This issue may allow an attacker using this library to cause a denial of service problem due to a missing check at a function return.

A flaw was found in the QEMU built-in VNC server while processing ClientCutText messages. The qemu_clipboard_request() function can be reached before vnc_server_cut_text_caps() was called and had the chance to initialize the clipboard peer, leading to a NULL pointer dereference. This could allow a malicious authenticated VNC client to crash QEMU and trigger a denial of service.