Important: qemu security update (Amazon Linux 2)

Package updates are available for Amazon Linux 2 that fix the following vulnerabilities: CVE-2026-97889: hw/display/vga: fix OOB writes after external surface resize CVE-2026-18609: A flaw was found in the USB CCID smartcard reader device emulation (hw/usb/dev-smartcard-reader.c) in QEMU. A guest can submit an interrupt IN transfer shorter than the 2-byte RDR_to_PC_NotifySlotChange message; usb_packet_copy() asserts that the packet has enough space, so a zero- or one-byte request triggers an assertion failure, crashing QEMU. This may result in a denial of service of the QEMU process. CVE-2026-18410: A flaw was found in the USB CCID (smartcard reader) device emulation (hw/usb/dev-smartcard-reader.c) in QEMU. For each PC_to_RDR_XfrBlock APDU received from the guest, ccid_on_apdu_from_guest() queues a pending answer without checking whether the slot is already busy. A guest that submits XfrBlock messages faster than the asynchronous card backend can process them can overflow the 128-entry pending-answers ring buffer, triggering an assertion failure in ccid_add_pending_answer() that aborts the QEMU process. This may result in a denial of service of the QEMU process. The flaw was introduced in QEMU 0.15.0 and fixed in 11.1.3 and 10.0.15. CVE-2026-18204: An out-of-bounds read was found in the USB CCID smartcard reader device (hw/usb/dev-smartcard-reader.c) in QEMU. ccid_bulk_in_get() decremented the pending bulk-in slot count when a ring slot became active instead of when it was released, allowing a malicious guest to fill the bulk-in ring, partially read a slot, and then reuse the still-active slot with a shorter response. The resulting stale position exceeds the new buffer length, causing an unsigned-integer underflow in ccid_bulk_in_copy_to_guest() that reads past the response buffer and can disclose host process memory to the guest or crash the QEMU process. The flaw was introduced in QEMU 0.15.0 and fixed in 11.1.3 and 10.0.15. CVE-2026-120831: A flaw was found in libslirp in if_output(). When moving a session from the fast queue to the batch queue, the code unlinked and reinserted an arbitrary packet via ifm->m_nextpkt instead of the session queue head, corrupting queue pointers. A guest generating burst traffic could crash the host networking process, causing a denial of service. CVE-2026-120830: A flaw was found in libslirp in icmp_forward_error(). When building an ICMP error response, the length of the quoted original IPv4 packet was taken from the IP header without clamping it to the actual buffer length. A truncated or malformed packet could cause an out-of-bounds heap read, leaking host memory into the ICMP error packet returned to a guest or container. CVE-2026-111819: hw/usb/hcd-xhci: More reentrancy guard fixes for the XHCI code CVE-2026-101291: A flaw was found in QEMU's websocket I/O channel (QIOChannelWebsock in io/channel-websock.c). The websocket server reads encoded data from a connected client into an input buffer and decodes it into a separate buffer, but the size limit is enforced only on the encoded-input buffer and not on the decoded-input buffer. A client that connects to a QEMU websocket endpoint -- such as a VNC server or a character-device socket backend configured with websocket=on -- and sends data that is not consumed can cause the decoded-input buffer to grow without bound, exhausting host memory and leading to a denial of service.