cbcvebase.
CVE-2025-40245
published 2025-12-04

CVE-2025-40245: In the Linux kernel, the following vulnerability has been resolved: nios2: ensure that memblock.current_limit is set when setting pfn limits On nios2, with…

PriorityP339high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.15%
4.8th percentile
In the Linux kernel, the following vulnerability has been resolved: nios2: ensure that memblock.current_limit is set when setting pfn limits On nios2, with CONFIG_FLATMEM set, the kernel relies on memblock_get_current_limit() to determine the limits of mem_map, in particular for max_low_pfn. Unfortunately, memblock.current_limit is only default initialized to MEMBLOCK_ALLOC_ANYWHERE at this point of the bootup, potentially leading to situations where max_low_pfn can erroneously exceed the value of max_pfn and, thus, the valid range of available DRAM. This can in turn cause kernel-level paging failures, e.g.: [ 76.900000] Unable to handle kernel paging request at virtual address 20303000 [ 76.900000] ea = c0080890, ra = c000462c, cause = 14 [ 76.900000] Kernel panic - not syncing: Oops [ 76.900000] ---[ end Kernel panic - not syncing: Oops ]--- This patch fixes this by pre-calculating memblock.current_limit based on the upper limits of the available memory ranges via adjust_lowmem_bounds, a simplified version of the equivalent implementation within the arm architecture.

Affected

26 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.158-1 (bookworm)linux 6.1.158-1 (bookworm)
linuxlinux
linuxlinux>= 7f7bc20bc41a4fbcd2db75b375ac95e5faf958ae < 25f09699edd360b534ccae16bc276c3b52c471f325f09699edd360b534ccae16bc276c3b52c471f3
linuxlinux>= 7f7bc20bc41a4fbcd2db75b375ac95e5faf958ae < 5c3e38a367822f036227dd52bac82dc4a05157e25c3e38a367822f036227dd52bac82dc4a05157e2
linuxlinux>= 7f7bc20bc41a4fbcd2db75b375ac95e5faf958ae < b1ec9faef7e36269ca3ec890972a78effbaeb975b1ec9faef7e36269ca3ec890972a78effbaeb975
linuxlinux>= 7f7bc20bc41a4fbcd2db75b375ac95e5faf958ae < 90f5f715550e07cd6a51f80fc3f062d832c8c99790f5f715550e07cd6a51f80fc3f062d832c8c997
linuxlinux>= 7f7bc20bc41a4fbcd2db75b375ac95e5faf958ae < 8912814f14e298b83df072fecc1f7ed1b63b1b2c8912814f14e298b83df072fecc1f7ed1b63b1b2c
linuxlinux>= 7f7bc20bc41a4fbcd2db75b375ac95e5faf958ae < a20b83cf45be2057f3d073506779e52c7fa17f94a20b83cf45be2057f3d073506779e52c7fa17f94
linuxlinux_kernel>= 0 < 6.1.158-16.1.158-1
linuxlinux_kernel>= 0 < 6.12.57-16.12.57-1
linuxlinux_kernel>= 0 < 6.17.6-16.17.6-1
linuxlinux_kernel>= 0 < 5.15.0-170.1805.15.0-170.180
linuxlinux_kernel>= 0 < 6.8.0-106.1066.8.0-106.106
linuxlinux_kernel>= 0 < 6.17.0-14.146.17.0-14.14
linuxlinux_kernel>= 5.12.0 < 5.15.1965.15.196
linuxlinux_kernel>= 5.16.0 < 6.1.1586.1.158
linuxlinux_kernel>= 6.13.0 < 6.17.66.17.6
linuxlinux_kernel>= 6.2.0 < 6.6.1156.6.115
linuxlinux_kernel>= 6.7.0 < 6.12.566.12.56
msrcazl3_kernel_6.6.112.1-2_on_azure_linux_3.0
ubuntulinux-aws
ubuntulinux-azure-5.15
ubuntulinux-intel-iotg-5.15
ubuntulinux-oracle
ubuntulinux-xilinx

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_ubuntu7.8HIGH
vendor_msrc5.5MEDIUM
Stop checking back — get the weekly exploitation signal.

Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.