CVE-2026-43025 (GCVE-0-2026-43025)

Vulnerability from cvelistv5 – Published: 2026-05-01 14:15 – Updated: 2026-05-03 05:46
VLAI?
Title
netfilter: ctnetlink: ignore explicit helper on new expectations
Summary
In the Linux kernel, the following vulnerability has been resolved: netfilter: ctnetlink: ignore explicit helper on new expectations Use the existing master conntrack helper, anything else is not really supported and it just makes validation more complicated, so just ignore what helper userspace suggests for this expectation. This was uncovered when validating CTA_EXPECT_CLASS via different helper provided by userspace than the existing master conntrack helper: BUG: KASAN: slab-out-of-bounds in nf_ct_expect_related_report+0x2479/0x27c0 Read of size 4 at addr ffff8880043fe408 by task poc/102 Call Trace: nf_ct_expect_related_report+0x2479/0x27c0 ctnetlink_create_expect+0x22b/0x3b0 ctnetlink_new_expect+0x4bd/0x5c0 nfnetlink_rcv_msg+0x67a/0x950 netlink_rcv_skb+0x120/0x350 Allowing to read kernel memory bytes off the expectation boundary. CTA_EXPECT_HELP_NAME is still used to offer the helper name to userspace via netlink dump.
Severity ?
7.3 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: bd0779370588386e4a67ba5d0b176cfded8e6a53 , < e135f8e8212cbed12a03ab8dec77fa1247139897 (git)
Affected: bd0779370588386e4a67ba5d0b176cfded8e6a53 , < 2ea0f35f235f70c133ad61fe05ba013753b978c6 (git)
Affected: bd0779370588386e4a67ba5d0b176cfded8e6a53 , < 0f6c33697ccfac6499d0b7a4dbdec5d3a3a566cd (git)
Affected: bd0779370588386e4a67ba5d0b176cfded8e6a53 , < 187b6ec5229ea93cb04c4f6d3b52efc80f513d0d (git)
Affected: bd0779370588386e4a67ba5d0b176cfded8e6a53 , < 21a04c31db4057deec85fcd6cc63d720b38819c3 (git)
Affected: bd0779370588386e4a67ba5d0b176cfded8e6a53 , < 917b61fa2042f11e2af4c428e43f08199586633a (git)
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    Linux Linux Affected: 3.12
Unaffected: 0 , < 3.12 (semver)
Unaffected: 6.1.168 , ≤ 6.1.* (semver)
Unaffected: 6.6.134 , ≤ 6.6.* (semver)
Unaffected: 6.12.81 , ≤ 6.12.* (semver)
Unaffected: 6.18.22 , ≤ 6.18.* (semver)
Unaffected: 6.19.12 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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{
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          "programFiles": [
            "net/netfilter/nf_conntrack_netlink.c"
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    "dateReserved": "2026-05-01T14:12:55.976Z",
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  }
}


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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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