Vulnerability Description
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.
References
- https://git.kernel.org/stable/c/0bf756ae1e69fec5e6332c37830488315d6d771b
- https://git.kernel.org/stable/c/2327a3d6f65ce2fe2634546dde4a25ef52296fec
- https://git.kernel.org/stable/c/2da805a61ef5272a2773775ce14c3650adb84248
- https://git.kernel.org/stable/c/75b16b2755e12999ad850756ddfb88ad4bfc7186
- https://git.kernel.org/stable/c/9bf27de51bd6db5ff827780ec0eba55de230ba45
- https://git.kernel.org/stable/c/b056f971bd72b373b7ae2025a8f3bd18f69653d3
- https://git.kernel.org/stable/c/c14cf41094136691c92ef756872570645d61f4a1
- https://git.kernel.org/stable/c/f28dde240160f3c48a50d641d210ed6a3b9596ed
FAQ
What is CVE-2025-40363?
CVE-2025-40363 is a documented vulnerability. 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()...
How severe is CVE-2025-40363?
CVSS scoring is not yet available for CVE-2025-40363. Check NVD for updates.
Is there a patch for CVE-2025-40363?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.