Vulnerability Details CVE-2026-31664
In the Linux kernel, the following vulnerability has been resolved:
xfrm: clear trailing padding in build_polexpire()
build_expire() clears the trailing padding bytes of struct
xfrm_user_expire after setting the hard field via memset_after(),
but the analogous function build_polexpire() does not do this for
struct xfrm_user_polexpire.
The padding bytes after the __u8 hard field are left
uninitialized from the heap allocation, and are then sent to
userspace via netlink multicast to XFRMNLGRP_EXPIRE listeners,
leaking kernel heap memory contents.
Add the missing memset_after() call, matching build_expire().
Exploit prediction scoring system (EPSS) score
EPSS Score 0.0
EPSS Ranking 6.8%
CVSS Severity
References
- https://git.kernel.org/stable/c/71a98248c63c535eaa4d4c22f099b68d902006d0
- https://git.kernel.org/stable/c/ac6985903db047eaff54db929e4bf6b06782788e
- https://git.kernel.org/stable/c/b1dfd6b27df35ef4f87825aa5f607378d23ff0f2
- https://git.kernel.org/stable/c/c221ed63a2769a0af8bd849dfe25740048f34ef4
- https://git.kernel.org/stable/c/e1af65c669ebb1666c54576614c01a7f9ffcfff6
- https://git.kernel.org/stable/c/eda30846ea54f8ed218468e5480c8305ca645e37