CVE-2026-74624 (GCVE-0-2026-74624)

Vulnerability from cvelistv5 – Published: 2026-08-22 15:32 – Updated: 2026-08-25 05:40
VLAI
Title
netfilter: nf_conntrack: defer invalid log until after unlock
Summary
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_conntrack: defer invalid log until after unlock TCP and SCTP conntrack paths can emit invalid-packet logs while ct->lock is still held. When invalid logging is routed to nfnetlink_log and conntrack export is enabled, the log path can re-enter conntrack netlink glue and dump the same conntrack again. Protocol attribute dumping may take ct->lock, so logging while holding that lock can deadlock. Defer the TCP invalid logs by storing only the minimal log context while ct->lock is held and emitting the log after unlocking. Also make the TCP timeout-lowering invalid path return whether a log is needed, then emit that log after unlocking. Do the same for the SCTP invalid state-transition log that can be reached while ct->lock is held. Add a lockdep assertion to nf_ct_l4proto_log_invalid() so future callers that log invalid conntracks while holding ct->lock are caught outside TCP and SCTP as well.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: d9a6f0d0df1899ff9086a57abc600e414f4b8cdd , < ca97360eba4b3dc67f1804625542f4ccc774242a (git)
Affected: d9a6f0d0df1899ff9086a57abc600e414f4b8cdd , < 63853eb20bba4e00b7cd0b8cfc19337bbaaf5037 (git)
Affected: d9a6f0d0df1899ff9086a57abc600e414f4b8cdd , < 9480fcf70a5aa9d320088a01c95df0e5e6391f4a (git)
Affected: d9a6f0d0df1899ff9086a57abc600e414f4b8cdd , < 0424186d570aa4d1ad17f516afb86bd9eaa4f42e (git)
Affected: d9a6f0d0df1899ff9086a57abc600e414f4b8cdd , < c0224327b7cbed9d3198e8dbec847281053dcd06 (git)
Affected: d9a6f0d0df1899ff9086a57abc600e414f4b8cdd , < 2d19b95c9723001f214f7a47d67b09f46238f200 (git)
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Linux Linux Affected: 6.1
Unaffected: 0 , < 6.1 (semver)
Unaffected: 6.1.184 , ≤ 6.1.* (semver)
Unaffected: 6.6.152 , ≤ 6.6.* (semver)
Unaffected: 6.12.104 , ≤ 6.12.* (semver)
Unaffected: 6.18.45 , ≤ 6.18.* (semver)
Unaffected: 7.1.9 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
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{
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          "product": "Linux",
          "programFiles": [
            "net/netfilter/nf_conntrack_proto.c",
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          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_conntrack: defer invalid log until after unlock\n\nTCP and SCTP conntrack paths can emit invalid-packet logs while ct-\u003elock\nis still held.\n\nWhen invalid logging is routed to nfnetlink_log and conntrack export is\nenabled, the log path can re-enter conntrack netlink glue and dump the\nsame conntrack again. Protocol attribute dumping may take ct-\u003elock, so\nlogging while holding that lock can deadlock.\n\nDefer the TCP invalid logs by storing only the minimal log context while\nct-\u003elock is held and emitting the log after unlocking. Also make the TCP\ntimeout-lowering invalid path return whether a log is needed, then emit\nthat log after unlocking.\n\nDo the same for the SCTP invalid state-transition log that can be reached\nwhile ct-\u003elock is held.\n\nAdd a lockdep assertion to nf_ct_l4proto_log_invalid() so future callers\nthat log invalid conntracks while holding ct-\u003elock are caught outside TCP\nand SCTP as well."
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    "cveId": "CVE-2026-74624",
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    "dateReserved": "2026-08-15T05:44:03.921Z",
    "dateUpdated": "2026-08-25T05:40:47.114Z",
    "state": "PUBLISHED"
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Also make the TCP\\ntimeout-lowering invalid path return whether a log is needed, then emit\\nthat log after unlocking.\\n\\nDo the same for the SCTP invalid state-transition log that can be reached\\nwhile ct-\u003elock is held.\\n\\nAdd a lockdep assertion to nf_ct_l4proto_log_invalid() so future callers\\nthat log invalid conntracks while holding ct-\u003elock are caught outside TCP\\nand SCTP as well.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"net/netfilter/nf_conntrack_proto.c\",\"net/netfilter/nf_conntrack_proto_sctp.c\",\"net/netfilter/nf_conntrack_proto_tcp.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"d9a6f0d0df1899ff9086a57abc600e414f4b8cdd\",\"lessThan\":\"ca97360eba4b3dc67f1804625542f4ccc774242a\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"d9a6f0d0df1899ff9086a57abc600e414f4b8cdd\",\"lessThan\":\"63853eb20bba4e00b7cd0b8cfc19337bbaaf5037\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"d9a6f0d0df1899ff9086a57abc600e414f4b8cdd\",\"lessThan\":\"9480fcf70a5aa9d320088a01c95df0e5e6391f4a\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"d9a6f0d0df1899ff9086a57abc600e414f4b8cdd\",\"lessThan\":\"0424186d570aa4d1ad17f516afb86bd9eaa4f42e\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"d9a6f0d0df1899ff9086a57abc600e414f4b8cdd\",\"lessThan\":\"c0224327b7cbed9d3198e8dbec847281053dcd06\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"d9a6f0d0df1899ff9086a57abc600e414f4b8cdd\",\"lessThan\":\"2d19b95c9723001f214f7a47d67b09f46238f200\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"net/netfilter/nf_conntrack_proto.c\",\"net/netfilter/nf_conntrack_proto_sctp.c\",\"net/netfilter/nf_conntrack_proto_tcp.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"6.1\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"6.1\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.184\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.152\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.104\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.45\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.9\",\"lessThanOrEqual\":\"7.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.2\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":7.5,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":3.6}]},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/0424186d570aa4d1ad17f516afb86bd9eaa4f42e\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/2d19b95c9723001f214f7a47d67b09f46238f200\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/63853eb20bba4e00b7cd0b8cfc19337bbaaf5037\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/9480fcf70a5aa9d320088a01c95df0e5e6391f4a\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/c0224327b7cbed9d3198e8dbec847281053dcd06\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/ca97360eba4b3dc67f1804625542f4ccc774242a\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-25T08:51:19+00:00",
      "cve": "CVE-2026-74624",
      "id": "CVE-2026-74624",
      "initial_release_date": "2026-08-22T00:00:00+00:00",
      "product_status:known_affected": "226",
      "product_status:known_not_affected": "48",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: netfilter: nf_conntrack: defer invalid log until after unlock",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74624.json",
      "version": "3"
    }
  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • 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.


Detection rules are retrieved from Rulezet.