Qemu: virtio: dma reentrancy issue leads to double free vulnerability
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.
Qemu: 9pfs: improper access control on special files
A flaw was found in the 9p passthrough filesystem (9pfs) implementation in QEMU. The 9pfs server did not prohibit opening special files on the host side, potentially allowing a malicious client to escape from the exported 9p tree by creating and opening a device file in the shared folder.
Qemu: improper ide controller reset can lead to mbr overwrite
A bug in QEMU could cause a guest I/O operation otherwise addressed to an arbitrary disk offset to be targeted to offset 0 instead (potentially overwriting the VM's boot code). This could be used, for example, by L2 guests with a virtual disk (vdiskL2) stored on a virtual disk of an L1 (vdiskL1) hypervisor to read and/or write data to LBA 0 of vdiskL1, potentially gaining control of L1 at its next reboot.
Heap buffer overflow in virtio_crypto_sym_op_helper()
A flaw was found in the QEMU virtual crypto device while handling data encryption/decryption requests in virtio_crypto_handle_sym_req. There is no check for the value of `src_len` and `dst_len` in virtio_crypto_sym_op_helper, potentially leading to a heap buffer overflow when the two values differ.
Qemu: 9pfs: suid/sgid bits not dropped on file write
A flaw was found in the 9p passthrough filesystem (9pfs) implementation in QEMU. When a local user in the guest writes an executable file with SUID or SGID, none of these privileged bits are correctly dropped. As a result, in rare circumstances, this flaw could be used by malicious users in the guest to elevate their privileges within the guest and help a host local user to elevate privileges on the host.
Qemu: e1000e: heap use-after-free in e1000e_write_packet_to_guest()
A DMA reentrancy issue leading to a use-after-free error was found in the e1000e NIC emulation code in QEMU. This issue could allow a privileged guest user to crash the QEMU process on the host, resulting in a denial of service.
Improper i/o watch removal in tls handshake can lead to remote unauthenticated denial of service
A flaw was found in the QEMU built-in VNC server. When a client connects to the VNC server, QEMU checks whether the current number of connections crosses a certain threshold and if so, cleans up the previous connection. If the previous connection happens to be in the handshake phase and fails, QEMU cleans up the connection again, resulting in a NULL pointer dereference issue. This could allow a remote unauthenticated client to cause a denial of service.
Qemu: lsi53c895a: dma reentrancy issue leads to stack overflow
A vulnerability in the lsi53c895a device affects the latest version of qemu. A DMA-MMIO reentrancy problem may lead to memory corruption bugs like stack overflow or use-after-free.
An out-of-bounds read flaw was found in the QXL display device emulation in QEMU. The qxl_phys2virt() function does not check the size of the structure pointed to by the guest physical address, potentially reading past the end of the bar space into adjacent pages. A malicious guest user could use this flaw to crash the QEMU process on the host causing a denial of service condition.
An off-by-one read/write issue was found in the SDHCI device of QEMU. It occurs when reading/writing the Buffer Data Port Register in sdhci_read_dataport and sdhci_write_dataport, respectively, if data_count == block_size. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service condition.
Media · CVSS 4.4EPSS 0,21%Sin corrección publicada
CVE-2021-3735
A deadlock issue was found in the AHCI controller device of QEMU. It occurs on a software reset (ahci_reset_port) while handling a host-to-device Register FIS (Frame Information Structure) packet from the guest. A privileged user inside the guest could use this flaw to hang the QEMU process on the host, resulting in a denial of service condition. The highest threat from this vulnerability is to system availability.
An infinite loop flaw was found in the USB xHCI controller emulation of QEMU while computing the length of the Transfer Request Block (TRB) Ring. This flaw allows a privileged guest user to hang the QEMU process on the host, resulting in a denial of service.
Media · CVSS 6.5EPSS 0,31%Sin corrección publicada
CVE-2019-12067
The ahci_commit_buf function in ide/ahci.c in QEMU allows attackers to cause a denial of service (NULL dereference) when the command header 'ad->cur_cmd' is null.
A NULL pointer dereference flaw was found in the megasas-gen2 SCSI host bus adapter emulation of QEMU in versions before and including 6.0. This issue occurs in the megasas_command_cancelled() callback function while dropping a SCSI request. This flaw allows a privileged guest user to crash the QEMU process on the host, resulting in a denial of service. The highest threat from this vulnerability is to system availability.
Media · CVSS 5.5EPSS 0,41%Sin corrección publicada
CVE-2021-20255
A stack overflow via an infinite recursion vulnerability was found in the eepro100 i8255x device emulator of QEMU. This issue occurs while processing controller commands due to a DMA reentry issue. This flaw allows a guest user or process to consume CPU cycles or crash the QEMU process on the host, resulting in a denial of service. The highest threat from this vulnerability is to system availability.
The QMP guest_exec command in QEMU 4.0.0 and earlier is prone to OS command injection, which allows the attacker to achieve code execution, denial of service, or information disclosure by sending a crafted QMP command to the listening server. Note: This has been disputed as a non-issue since QEMU's -qmp interface is meant to be used by trusted users. If one is able to access this interface via a tcp socket open to the internet, then it is an insecure configuration issue
Crítica · CVSS 9.8EPSS 23,04%Código de explotación públicoSin corrección publicada
CVE-2019-12928
The QMP migrate command in QEMU version 4.0.0 and earlier is vulnerable to OS command injection, which allows the remote attacker to achieve code execution, denial of service, or information disclosure by sending a crafted QMP command to the listening server. Note: This has been disputed as a non-issue since QEMU's -qmp interface is meant to be used by trusted users. If one is able to access this interface via a tcp socket open to the internet, then it is an insecure configuration issue