Description
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().
Affected products
linux: linux kernel
References10
- git.kernel.org/stable/c/71a98248c63c535eaa4d4c22f099b68d902006d0 Patch
- git.kernel.org/stable/c/ac6985903db047eaff54db929e4bf6b06782788e Patch
- git.kernel.org/stable/c/b1dfd6b27df35ef4f87825aa5f607378d23ff0f2 Patch
- git.kernel.org/stable/c/c221ed63a2769a0af8bd849dfe25740048f34ef4 Patch
- git.kernel.org/stable/c/e1af65c669ebb1666c54576614c01a7f9ffcfff6 Patch
- git.kernel.org/stable/c/eda30846ea54f8ed218468e5480c8305ca645e37 Patch
- git.kernel.org/stable/c/a5127501c8d30b5728791b1e340284ca5c9cc4bd
- git.kernel.org/stable/c/e6f4ffe8596947a595c9544e73a73adcb0568b88
- cert-portal.siemens.com/productcert/html/ssa-019113.html
- cert-portal.siemens.com/productcert/html/ssa-082556.html
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 2 · as of 13 November 2026
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