In the Linux kernel, the following vulnerability has been resolved: net: qualcomm: rmnet: validate MAP frame length before ingress parsing When ingress deaggregation is disabled, rmnet_map_ingress_handler() passes the skb straight to __rmnet_map_ingress_handler(), skipping the length validation that rmnet_map_deaggregate() performs on the aggregated path. The parser then dereferences the MAP header and csum header/trailer based on the on-wire pkt_len without checking skb->len, so a short frame is read out of bounds: BUG: KASAN: slab-out-of-bounds in rmnet_map_checksum_downlink_packet Read of size 1 at addr ffff88801118ed00 by task exploit/147 Call Trace: ... rmnet_map_checksum_downlink_packet (drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c:413) __rmnet_map_ingress_handler (drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c:96) rmnet_rx_handler (drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c:129) __netif_receive_skb_core.constprop.0 (net/core/dev.c:6089) netif_receive_skb (net/core/dev.c:6460) tun_get_user (drivers/net/tun.c:1955) tun_chr_write_iter (drivers/net/tun.c:2001) vfs_write (fs/read_write.c:688) ksys_write (fs/read_write.c:740) do_syscall_64 (arch/x86/entry/syscall_64.c:94) ... Factor that validation out of rmnet_map_deaggregate() into rmnet_map_validate_packet_len() and run it on the no-aggregation path too. The MAP header is bounds-checked first, since this path can receive a frame shorter than the header.

A flaw was found in the Linux kernel's Qualcomm rmnet component. This vulnerability occurs because the system does not properly check the size of incoming network packets, specifically MAP frames, when a certain network feature (ingress deaggregation) is turned off. A remote attacker could exploit this by sending a specially crafted, undersized network packet. This can cause the system to read beyond its allocated memory, leading to a system crash and making the service unavailable (Denial of Service).

Red Hat Enterprise Linux 10 Not affected kernel Red Hat Enterprise Linux 6 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Not affected kernel Red Hat Enterprise Linux 8 Not affected kernel-rt Red Hat Enterprise Linux 9 Not affected kernel Red Hat Enterprise Linux 9 Not affected kernel-rt Red Hat Hardened Images Not affected erlang27 https://www.cve.org/CVERecord?id=CVE-2026-64550 https://nvd.nist.gov/vuln/detail/CVE-2026-64550 https://lore.kernel.org/linux-cve-announce/2026072737-CVE-2026-64550-e84a@gregkh/T