A flaw was found in QEMU in the implementation of the Pointer Authentication (PAuth) support for ARM introduced in version 4.0 and fixed in version 5.0.0. A general failure of the signature generation process caused every PAuth-enforced pointer to be signed with the same signature. A local attacker could obtain the signature of a protected pointer and abuse this flaw to bypass PAuth protection for all programs running on QEMU.

The remote CentOS Linux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the qemu-kvm-6.1.0-3.el9 build changelog.

  - use-after-free during packet reassembly [rhel-av-8]) (CVE-2019-15890)

  - A flaw was found in QEMU in the implementation of the Pointer Authentication (PAuth) support for ARM     introduced in version 4.0 and fixed in version 5.0.0. A general failure of the signature generation     process caused every PAuth-enforced pointer to be signed with the same signature. A local attacker could     obtain the signature of a protected pointer and abuse this flaw to bypass PAuth protection for all     programs running on QEMU. (CVE-2020-10702)

  - A potential DoS flaw was found in the virtio-fs shared file system daemon (virtiofsd) implementation of     the QEMU version >= v5.0. Virtio-fs is meant to share a host file system directory with a guest via     virtio-fs device. If the guest opens the maximum number of file descriptors under the shared directory, a     denial of service may occur. This flaw allows a guest user/process to cause this denial of service on the     host. (CVE-2020-10717)

  - An out-of-bounds read vulnerability was found in the SLiRP networking implementation of the QEMU emulator.
    This flaw occurs in the icmp6_send_echoreply() routine while replying to an ICMP echo request, also known     as ping. This flaw allows a malicious guest to leak the contents of the host memory, resulting in possible     information disclosure. This flaw affects versions of libslirp before 4.3.1. (CVE-2020-10756)

  - An assertion failure issue was found in the Network Block Device(NBD) Server in all QEMU versions before     QEMU 5.0.1. This flaw occurs when an nbd-client sends a spec-compliant request that is near the boundary     of maximum permitted request length. A remote nbd-client could use this flaw to crash the qemu-nbd server     resulting in a denial of service. (CVE-2020-10761)

  - out-of-bounds r/w access issue while processing usb packets [rhel-av-8.3.0]) (CVE-2020-14364)

  - OOB heap access via an unexpected response of iSCSI Server [rhel-av-8.2.0]) (CVE-2020-1711)

  - A use after free vulnerability in ip_reass() in ip_input.c of libslirp 4.2.0 and prior releases allows     crafted packets to cause a denial of service. (CVE-2020-1983)

  - A flaw was found in the memory management API of QEMU during the initialization of a memory region cache.
    This issue could lead to an out-of-bounds write access to the MSI-X table while performing MMIO     operations. A guest user may abuse this flaw to crash the QEMU process on the host, resulting in a denial     of service. This flaw affects QEMU versions prior to 5.2.0. (CVE-2020-27821)

  - A flaw was found in qemu. A host privilege escalation issue was found in the virtio-fs shared file system     daemon where a privileged guest user is able to create a device special file in the shared directory and     use it to r/w access host devices. (CVE-2020-35517)

  - OOB buffer access while emulating tcp protocols in tcp_emu() [rhel-av-8.2.0]) (CVE-2020-7039)

  - potential OOB access due to unsafe snprintf() usages [rhel-av-8.2.0]) (CVE-2020-8608)

  - An out-of-bounds heap buffer access issue was found in the ARM Generic Interrupt Controller emulator of     QEMU up to and including qemu 4.2.0on aarch64 platform. The issue occurs because while writing an     interrupt ID to the controller memory area, it is not masked to be 4 bits wide. It may lead to the said     issue while updating controller state fields and their subsequent processing. A privileged guest user may     use this flaw to crash the QEMU process on the host resulting in DoS scenario. (CVE-2021-20221)

  - A flaw was found in the virtio-fs shared file system daemon (virtiofsd) of QEMU. The new 'xattrmap' option     may cause the 'security.capability' xattr in the guest to not drop on file write, potentially leading to a     modified, privileged executable in the guest. In rare circumstances, this flaw could be used by a     malicious user to elevate their privileges within the guest. (CVE-2021-20263)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

According to the versions of the qemu packages installed, the EulerOS Virtualization installation on the remote host is affected by the following vulnerabilities :

  - In QEMU through 5.0.0, an integer overflow was found in     the SM501 display driver implementation. This flaw     occurs in the COPY_AREA macro while handling MMIO write     operations through the sm501_2d_engine_write()     callback. A local attacker could abuse this flaw to     crash the QEMU process in sm501_2d_operation() in     hw/display/sm501.c on the host, resulting in a denial     of service.(CVE-2020-12829)

  - slirp.c in libslirp through 4.3.1 has a buffer     over-read because it tries to read a certain amount of     header data even if that exceeds the total packet     length.(CVE-2020-29130)

  - ncsi.c in libslirp through 4.3.1 has a buffer over-read     because it tries to read a certain amount of header     data even if that exceeds the total packet     length.(CVE-2020-29129)

  - hw/net/e1000e_core.c in QEMU 5.0.0 has an infinite loop     via an RX descriptor with a NULL buffer     address.(CVE-2020-28916)

  - ati_2d_blt in hw/display/ati_2d.c in QEMU 4.2.1 can     encounter an outside-limits situation in a calculation.
    A guest can crash the QEMU process.(CVE-2020-27616)

  - eth_get_gso_type in net/eth.c in QEMU 4.2.1 allows     guest OS users to trigger an assertion failure. A guest     can crash the QEMU process via packet data that lacks a     valid Layer 3 protocol.(CVE-2020-27617)

  - A reachable assertion issue was found in the USB EHCI     emulation code of QEMU. It could occur while processing     USB requests due to missing handling of DMA memory map     failure. A malicious privileged user within the guest     may abuse this flaw to send bogus USB requests and     crash the QEMU process on the host, resulting in a     denial of service.(CVE-2020-25723)

  - hw/usb/hcd-ohci.c in QEMU 5.0.0 has a stack-based     buffer over-read via values obtained from the host     controller driver.(CVE-2020-25624)

  - hw/usb/hcd-ohci.c in QEMU 5.0.0 has an infinite loop     when a TD list has a loop.(CVE-2020-25625)

  - In libslirp 4.1.0, as used in QEMU 4.2.0, tcp_subr.c     misuses snprintf return values, leading to a buffer     overflow in later code.(CVE-2020-8608)

  - tcp_emu in tcp_subr.c in libslirp 4.1.0, as used in     QEMU 4.2.0, mismanages memory, as demonstrated by IRC     DCC commands in EMU_IRC. This can cause a heap-based     buffer overflow or other out-of-bounds access which can     lead to a DoS or potential execute arbitrary     code.(CVE-2020-7039)

  - ip_reass in ip_input.c in libslirp 4.0.0 has a     heap-based buffer overflow via a large packet because     it mishandles a case involving the first     fragment.(CVE-2019-14378)

  - A flaw was found in the memory management API of QEMU     during the initialization of a memory region cache.
    This issue could lead to an out-of-bounds write access     to the MSI-X table while performing MMIO operations. A     guest user may abuse this flaw to crash the QEMU     process on the host, resulting in a denial of service.
    This flaw affects QEMU versions prior to     5.2.0.(CVE-2020-27821)

  - QEMU: reachable assertion failure in     net_tx_pkt_add_raw_fragment() in hw/net/net_tx_pkt.c     (CVE-2020-16092)

  - hw/pci/pci.c in QEMU 4.2.0 allows guest OS users to     trigger an out-of-bounds access by providing an address     near the end of the PCI configuration     space(CVE-2020-13791)

  - qmp_guest_file_read in qga/commands-posix.c and     qga/commands-win32.c in qemu-ga (aka QEMU Guest Agent)     in QEMU 2.12.50 has an integer overflow causing a     g_malloc0() call to trigger a segmentation fault when     trying to allocate a large memory chunk. The     vulnerability can be exploited by sending a crafted QMP     command (including guest-file-read with a large count     value) to the agent via the listening     socket.(CVE-2018-12617)

  - sd_wp_addr in hw/sd/sd.c in QEMU 4.2.0 uses an     unvalidated address, which leads to an out-of-bounds     read during sdhci_write() operations. A guest OS user     can crash the QEMU process.(CVE-2020-13253)

  - QEMU 4.1.0 has a memory leak in zrle_compress_data in     ui/vnc-enc-zrle.c during a VNC disconnect operation     because libz is misused, resulting in a situation where     memory allocated in deflateInit2 is not freed in     deflateEnd.(CVE-2019-20382)

  - An integer overflow was found in QEMU 4.0.1 through     4.2.0 in the way it implemented ATI VGA emulation. This     flaw occurs in the ati_2d_blt() routine in     hw/display/ati-2d.c while handling MMIO write     operations through the ati_mm_write() callback. A     malicious guest could abuse this flaw to crash the QEMU     process, resulting in a denial of     service.(CVE-2020-11869)

  - This vulnerability has been modified since it was last     analyzed by the NVD. It is awaiting reanalysis which     may result in further changes to the information     provided.(CVE-2020-13659)

  - A flaw was found in QEMU in the implementation of the     Pointer Authentication (PAuth) support for ARM     introduced in version 4.0 and fixed in version 5.0.0. A     general failure of the signature generation process     caused every PAuth-enforced pointer to be signed with     the same signature. A local attacker could obtain the     signature of a protected pointer and abuse this flaw to     bypass PAuth protection for all programs running on     QEMU.(CVE-2020-10702)

  - hw/net/xgmac.c in the XGMAC Ethernet controller in QEMU     before 07-20-2020 has a buffer overflow. This occurs     during packet transmission and affects the highbank and     midway emulated machines. A guest user or process could     use this flaw to crash the QEMU process on the host,     resulting in a denial of service or potential     privileged code execution. This was fixed in commit     5519724a13664b43e225ca05351c60b4468e4555.(CVE-2020-1586     3)

  - In QEMU 5.0.0 and earlier, megasas_lookup_frame in     hw/scsi/megasas.c has an out-of-bounds read via a     crafted reply_queue_head field from a guest OS     user.(CVE-2020-13362)

  - ** DISPUTED ** An issue was discovered in ide_dma_cb()     in hw/ide/core.c in QEMU 2.4.0 through 4.2.0. The guest     system can crash the QEMU process in the host system     via a special SCSI_IOCTL_SEND_COMMAND. It hits an     assertion that implies that the size of successful DMA     transfers there must be a multiple of 512 (the size of     a sector). NOTE: a member of the QEMU security team     disputes the significance of this issue because a     'privileged guest user has many ways to cause similar     DoS effect, without triggering this     assert.'(CVE-2019-20175)

  - In QEMU 5.0.0 and earlier, es1370_transfer_audio in     hw/audio/es1370.c does not properly validate the frame     count, which allows guest OS users to trigger an     out-of-bounds access during an es1370_write()     operation.(CVE-2020-13361)

  - rom_copy() in hw/core/loader.c in QEMU 4.1.0 does not     validate the relationship between two addresses, which     allows attackers to trigger an invalid memory copy     operation.(CVE-2020-13765)

  - libslirp 4.0.0, as used in QEMU 4.1.0, has a     use-after-free in ip_reass in     ip_input.c.(CVE-2019-15890)

  - A use after free vulnerability in ip_reass() in     ip_input.c of libslirp 4.2.0 and prior releases allows     crafted packets to cause a denial of     service.(CVE-2020-1983)

  - ati-vga in hw/display/ati.c in QEMU 4.2.0 allows guest     OS users to trigger infinite recursion via a crafted     mm_index value during an ati_mm_read or ati_mm_write     call.(CVE-2020-13800)

  - An out-of-bounds heap buffer access flaw was found in     the way the iSCSI Block driver in QEMU versions 2.12.0     before 4.2.1 handled a response coming from an iSCSI     server while checking the status of a Logical Address     Block (LBA) in an iscsi_co_block_status() routine. A     remote user could use this flaw to crash the QEMU     process, resulting in a denial of service or potential     execution of arbitrary code with privileges of the QEMU     process on the host.(CVE-2020-1711)

  - tftp.c in libslirp 4.1.0, as used in QEMU 4.2.0, does     not prevent ..\ directory traversal on     Windows.(CVE-2020-7211)

  - An out-of-bounds read vulnerability was found in the     SLiRP networking implementation of the QEMU emulator.
    This flaw occurs in the icmp6_send_echoreply() routine     while replying to an ICMP echo request, also known as     ping. This flaw allows a malicious guest to leak the     contents of the host memory, resulting in possible     information disclosure. This flaw affects versions of     libslirp before 4.3.1.(CVE-2020-10756)

Note that Tenable Network Security has extracted the preceding description block directly from the EulerOS security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

The remote Oracle Linux 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2021-9034 advisory.

    - Document CVE-2020-25723 as fixed (Mark Kanda)  [Orabug: 32222397]  {CVE-2020-25084} {CVE-2020-25723}
    - hw/net/e1000e: advance desc_offset in case of null descriptor (Prasad J Pandit)  [Orabug: 32217517]     {CVE-2020-28916}
    - libslirp: Update version to include CVE fixes (Mark Kanda)  [Orabug: 32208456] [Orabug: 32208462]     {CVE-2020-29129} {CVE-2020-29130}
    - Document CVE-2020-25624 as fixed (Mark Kanda)  [Orabug: 32212527]  {CVE-2020-25624} {CVE-2020-25625}
    - ati: check x y display parameter values (Prasad J Pandit)  [Orabug: 32108251]  {CVE-2020-27616}
    - hw: usb: hcd-ohci: check for processed TD before retire (Prasad J Pandit)  [Orabug: 31901690]     {CVE-2020-25625}
    - hw: usb: hcd-ohci: check len and frame_number variables (Prasad J Pandit)  [Orabug: 31901690]     {CVE-2020-25625}
    - hw: ehci: check return value of 'usb_packet_map' (Li Qiang)  [Orabug: 31901649]  {CVE-2020-25084}
    - hw: xhci: check return value of 'usb_packet_map' (Li Qiang)  [Orabug: 31901649]  {CVE-2020-25084}
    - usb: fix setup_len init (CVE-2020-14364) (Gerd Hoffmann)  [Orabug: 31848849]  {CVE-2020-14364}
    - Document CVE-2020-12829 and CVE-2020-14415 as fixed (Mark Kanda)  [Orabug: 31855502] [Orabug: 31855427]     {CVE-2020-12829} {CVE-2020-14415}
    - hw/net/xgmac: Fix buffer overflow in xgmac_enet_send() (Mauro Matteo Cascella)  [Orabug: 31667649]     {CVE-2020-15863}
    - hw/net/net_tx_pkt: fix assertion failure in net_tx_pkt_add_raw_fragment() (Mauro Matteo Cascella)     [Orabug: 31737809]  {CVE-2020-16092}
    - hw/sd/sdcard: Do not switch to ReceivingData if address is invalid (Philippe Mathieu-Daude)  [Orabug:
    31414336]  {CVE-2020-13253}
    - hw/sd/sdcard: Do not allow invalid SD card sizes (Philippe Mathieu-Daude)  [Orabug: 31414336]     {CVE-2020-13253}
    - libslirp: Update to v4.3.1 to fix CVE-2020-10756 (Karl Heubaum)  [Orabug: 31604999]  {CVE-2020-10756}
    - Document CVEs as fixed 2/2 (Karl Heubaum)  [Orabug: 30618035]  {CVE-2017-18043} {CVE-2018-10839}     {CVE-2018-11806} {CVE-2018-12617} {CVE-2018-15746} {CVE-2018-16847} {CVE-2018-16867} {CVE-2018-17958}     {CVE-2018-17962} {CVE-2018-17963} {CVE-2018-18849} {CVE-2018-19364} {CVE-2018-19489} {CVE-2018-3639}     {CVE-2018-5683} {CVE-2018-7550} {CVE-2018-7858} {CVE-2019-12068} {CVE-2019-15034} {CVE-2019-15890}     {CVE-2019-20382} {CVE-2020-10702} {CVE-2020-10761} {CVE-2020-11102} {CVE-2020-11869} {CVE-2020-13361}     {CVE-2020-13765} {CVE-2020-13800} {CVE-2020-1711} {CVE-2020-1983} {CVE-2020-8608}
    - Document CVEs as fixed 1/2 (Karl Heubaum)  [Orabug: 30618035]  {CVE-2017-10806} {CVE-2017-11334}     {CVE-2017-12809} {CVE-2017-13672} {CVE-2017-13673} {CVE-2017-13711} {CVE-2017-14167} {CVE-2017-15038}     {CVE-2017-15119} {CVE-2017-15124} {CVE-2017-15268} {CVE-2017-15289} {CVE-2017-16845} {CVE-2017-17381}     {CVE-2017-18030} {CVE-2017-2630} {CVE-2017-2633} {CVE-2017-5715} {CVE-2017-5753} {CVE-2017-5754}     {CVE-2017-5931} {CVE-2017-6058} {CVE-2017-7471} {CVE-2017-7493} {CVE-2017-8112} {CVE-2017-8309}     {CVE-2017-8379} {CVE-2017-8380} {CVE-2017-9503} {CVE-2017-9524} {CVE-2018-12126} {CVE-2018-12127}     {CVE-2018-12130} {CVE-2018-16872} {CVE-2018-20123} {CVE-2018-20124} {CVE-2018-20125} {CVE-2018-20126}     {CVE-2018-20191} {CVE-2018-20216} {CVE-2018-20815} {CVE-2019-11091} {CVE-2019-12155} {CVE-2019-14378}     {CVE-2019-3812} {CVE-2019-5008} {CVE-2019-6501} {CVE-2019-6778} {CVE-2019-8934} {CVE-2019-9824}
    - exec: set map length to zero when returning NULL (Prasad J Pandit)  [Orabug: 31439733]  {CVE-2020-13659}
    - megasas: use unsigned type for reply_queue_head and check index (Prasad J Pandit)  [Orabug: 31414338]     {CVE-2020-13362}
    - memory: Revert 'memory: accept mismatching sizes in memory_region_access_valid' (Michael S. Tsirkin)     [Orabug: 31439736] [Orabug: 31452202]  {CVE-2020-13754} {CVE-2020-13791}
    - Document CVE-2020-13765 as fixed (Karl Heubaum)  [Orabug: 31463250]  {CVE-2020-13765}
    - ati-vga: check mm_index before recursive call (CVE-2020-13800) (Prasad J Pandit)  [Orabug: 31452206]     {CVE-2020-13800}
    - es1370: check total frame count against current frame (Prasad J Pandit)  [Orabug: 31463235]     {CVE-2020-13361}
    - ati-vga: Fix checks in ati_2d_blt() to avoid crash (BALATON Zoltan)  [Orabug: 31238432]     {CVE-2020-11869}
    - libslirp: Update to stable-4.2 to fix CVE-2020-1983 (Karl Heubaum)  [Orabug: 31241227]  {CVE-2020-1983}
    - Document CVEs as fixed (Karl Heubaum)   {CVE-2019-12068} {CVE-2019-15034}
    - libslirp: Update to version 4.2.0 to fix CVEs (Karl Heubaum)  [Orabug: 30274592] [Orabug: 30869830]     {CVE-2019-15890} {CVE-2020-8608}
    - vnc: fix memory leak when vnc disconnect (Li Qiang)  [Orabug: 30996427]  {CVE-2019-20382}
    - iscsi: Cap block count from GET LBA STATUS (CVE-2020-1711) (Felipe Franciosi)  [Orabug: 31124035]     {CVE-2020-1711}

Tenable has extracted the preceding description block directly from the Oracle Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Ubuntu 16.04 LTS / 18.04 LTS / 20.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-4372-1 advisory.

    It was discovered that QEMU incorrectly handled bochs-display devices. A local attacker in a guest could     use this to cause a denial of service or possibly execute arbitrary code in the host. This issue only     affected Ubuntu 19.10. (CVE-2019-15034)

    It was discovered that QEMU incorrectly handled memory during certain VNC operations. A remote attacker     could possibly use this issue to cause QEMU to consume resources, resulting in a denial of service. This     issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 19.10. (CVE-2019-20382)

    It was discovered that QEMU incorrectly generated QEMU Pointer Authentication signatures on ARM. A local     attacker could possibly use this issue to bypass PAuth. This issue only affected Ubuntu 19.10.
    (CVE-2020-10702)

    Ziming Zhang discovered that QEMU incorrectly handled ATI VGA emulation. A local attacker in a guest could     use this issue to cause QEMU to crash, resulting in a denial of service. This issue only affected Ubuntu     20.04 LTS. (CVE-2020-11869)

    Aviv Sasson discovered that QEMU incorrectly handled Slirp networking. A remote attacker could use this     issue to cause QEMU to crash, resulting in a denial of service, or possibly execute arbitrary code. This     issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 19.10. (CVE-2020-1983)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Severity
191255	CentOS 9 : qemu-kvm-6.1.0-3.el9	Nessus	CentOS Local Security Checks	high
147700	EulerOS Virtualization 2.9.0 : qemu (EulerOS-SA-2021-1667)	Nessus	Huawei Local Security Checks	high
147523	EulerOS Virtualization 2.9.1 : qemu (EulerOS-SA-2021-1632)	Nessus	Huawei Local Security Checks	high
146269	Oracle Linux 7 : qemu (ELSA-2021-9034)	Nessus	Oracle Linux Local Security Checks	medium
136803	Ubuntu 16.04 LTS / 18.04 LTS / 20.04 LTS : QEMU vulnerabilities (USN-4372-1)	Nessus	Ubuntu Local Security Checks	medium

Detections

Analytics

CVE-2020-10702

medium

Tenable Plugins

high

high

high

medium

medium