cbcvebase.
CVE-2025-40363
published 2025-12-16

CVE-2025-40363: In the Linux kernel, the following vulnerability has been resolved: net: ipv6: fix field-spanning memcpy warning in AH output Fix field-spanning memcpy…

PriorityP421high7.8
EPSS
0.19%
8.6th percentile
In the Linux kernel, the following vulnerability has been resolved: net: ipv6: fix field-spanning memcpy warning in AH output Fix field-spanning memcpy warnings in ah6_output() and ah6_output_done() where extension headers are copied to/from IPv6 address fields, triggering fortify-string warnings about writes beyond the 16-byte address fields. memcpy: detected field-spanning write (size 40) of single field "&top_iph->saddr" at net/ipv6/ah6.c:439 (size 16) WARNING: CPU: 0 PID: 8838 at net/ipv6/ah6.c:439 ah6_output+0xe7e/0x14e0 net/ipv6/ah6.c:439 The warnings are false positives as the extension headers are intentionally placed after the IPv6 header in memory. Fix by properly copying addresses and extension headers separately, and introduce helper functions to avoid code duplication.

Affected

29 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.159-1 (bookworm)linux 6.1.159-1 (bookworm)
debianlinux-6.1< linux 6.1.159-1 (bookworm)linux 6.1.159-1 (bookworm)
linuxlinux
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 2da805a61ef5272a2773775ce14c3650adb842482da805a61ef5272a2773775ce14c3650adb84248
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 9bf27de51bd6db5ff827780ec0eba55de230ba459bf27de51bd6db5ff827780ec0eba55de230ba45
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 0bf756ae1e69fec5e6332c37830488315d6d771b0bf756ae1e69fec5e6332c37830488315d6d771b
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 75b16b2755e12999ad850756ddfb88ad4bfc718675b16b2755e12999ad850756ddfb88ad4bfc7186
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < f28dde240160f3c48a50d641d210ed6a3b9596edf28dde240160f3c48a50d641d210ed6a3b9596ed
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < c14cf41094136691c92ef756872570645d61f4a1c14cf41094136691c92ef756872570645d61f4a1
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < b056f971bd72b373b7ae2025a8f3bd18f69653d3b056f971bd72b373b7ae2025a8f3bd18f69653d3
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 2327a3d6f65ce2fe2634546dde4a25ef52296fec2327a3d6f65ce2fe2634546dde4a25ef52296fec
linuxlinux_kernel>= 0 < 5.10.247-15.10.247-1
linuxlinux_kernel>= 0 < 6.1.159-16.1.159-1
linuxlinux_kernel>= 0 < 6.12.63-16.12.63-1
linuxlinux_kernel>= 0 < 6.17.8-16.17.8-1
linuxlinux_kernel>= 0 < 5.15.0-173.1835.15.0-173.183
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>= 2.6.12 < 5.4.3025.4.302
linuxlinux_kernel>= 5.11.0 < 5.15.1975.15.197
linuxlinux_kernel>= 5.16.0 < 6.1.1596.1.159
linuxlinux_kernel>= 5.5.0 < 5.10.2475.10.247
linuxlinux_kernel>= 6.13.0 < 6.17.86.17.8
linuxlinux_kernel>= 6.2.0 < 6.6.1176.6.117
linuxlinux_kernel>= 6.7.0 < 6.12.586.12.58

CVSS provenance

osv7.8HIGH
vendor_ubuntu7.8HIGH
vendor_redhat5.5MEDIUM
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