CVE-2026-31664 (GCVE-0-2026-31664)

Vulnerability from cvelistv5 – Published: 2026-04-24 14:45 – Updated: 2026-04-24 14:45
VLAI?
Title
xfrm: clear trailing padding in build_polexpire()
Summary
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().
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < ac6985903db047eaff54db929e4bf6b06782788e (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < c221ed63a2769a0af8bd849dfe25740048f34ef4 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < eda30846ea54f8ed218468e5480c8305ca645e37 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < b1dfd6b27df35ef4f87825aa5f607378d23ff0f2 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < e1af65c669ebb1666c54576614c01a7f9ffcfff6 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 71a98248c63c535eaa4d4c22f099b68d902006d0 (git)
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    Linux Linux Affected: 2.6.12
Unaffected: 0 , < 2.6.12 (semver)
Unaffected: 6.1.169 , ≤ 6.1.* (semver)
Unaffected: 6.6.135 , ≤ 6.6.* (semver)
Unaffected: 6.12.82 , ≤ 6.12.* (semver)
Unaffected: 6.18.23 , ≤ 6.18.* (semver)
Unaffected: 6.19.13 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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        "dateUpdated": "2026-04-24T14:45:13.922Z",
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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