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CVE-2026-68300 (GCVE-0-2026-68300)

Vulnerability from cvelistv5 – Published: 2026-08-10 12:02 – Updated: 2026-08-19 16:32
VLAI
Title
sctp: auth: verify auth requirement when auth_chunk is NULL
Summary
In the Linux kernel, the following vulnerability has been resolved: sctp: auth: verify auth requirement when auth_chunk is NULL sctp_auth_chunk_verify() returns true unconditionally when chunk->auth_chunk is NULL, silently skipping authentication. This is incorrect when: 1. skb_clone() failed in the BH receive path, leaving auth_chunk NULL. In sctp_endpoint_bh_rcv() asoc is NULL for new connections, so the early sctp_auth_recv_cid() check cannot catch this. 2. No AUTH chunk precedes COOKIE-ECHO, so skb_clone() is never called and auth_chunk remains NULL. Fix by checking sctp_auth_recv_cid() when auth_chunk is NULL: if authentication is required, return false to drop the chunk; otherwise continue normally.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: bbd0d59809f923ea2b540cbd781b32110e249f6e , < a129792b3aef15002746c13522781d92ed3522c3 (git)
Affected: bbd0d59809f923ea2b540cbd781b32110e249f6e , < 5a022ac51ad83b4ce6c898f4b9eefc65bd26b247 (git)
Affected: bbd0d59809f923ea2b540cbd781b32110e249f6e , < 6caf0e8590c0bf05a76b0d387726adf3a6f3725c (git)
Affected: bbd0d59809f923ea2b540cbd781b32110e249f6e , < ec2e157fc9678a9bc411305a25aec3fd337d7efb (git)
Affected: bbd0d59809f923ea2b540cbd781b32110e249f6e , < 28c5fdce9dd955d2baf5e28987819b6d7cfaf646 (git)
Affected: bbd0d59809f923ea2b540cbd781b32110e249f6e , < 18957373920caf5cdaf5cf32e5d1d7a99ca7700a (git)
Affected: bbd0d59809f923ea2b540cbd781b32110e249f6e , < 83f5031f2a6a49d696eb4cc0898345d12f9c6451 (git)
Affected: bbd0d59809f923ea2b540cbd781b32110e249f6e , < 8e04823c120b376ef7dab14b60ebf6823aa16c14 (git)
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Linux Linux Affected: 2.6.24
Unaffected: 0 , < 2.6.24 (semver)
Unaffected: 5.10.265 , ≤ 5.10.* (semver)
Unaffected: 5.15.216 , ≤ 5.15.* (semver)
Unaffected: 6.1.183 , ≤ 6.1.* (semver)
Unaffected: 6.6.148 , ≤ 6.6.* (semver)
Unaffected: 6.12.101 , ≤ 6.12.* (semver)
Unaffected: 6.18.42 , ≤ 6.18.* (semver)
Unaffected: 7.1.6 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
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No AUTH chunk precedes COOKIE-ECHO, so skb_clone() is never\\n   called and auth_chunk remains NULL.\\n\\nFix by checking sctp_auth_recv_cid() when auth_chunk is NULL:\\nif authentication is required, return false to drop the chunk;\\notherwise continue normally.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"net/sctp/sm_statefuns.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"bbd0d59809f923ea2b540cbd781b32110e249f6e\",\"lessThan\":\"a129792b3aef15002746c13522781d92ed3522c3\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"bbd0d59809f923ea2b540cbd781b32110e249f6e\",\"lessThan\":\"5a022ac51ad83b4ce6c898f4b9eefc65bd26b247\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"bbd0d59809f923ea2b540cbd781b32110e249f6e\",\"lessThan\":\"6caf0e8590c0bf05a76b0d387726adf3a6f3725c\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"bbd0d59809f923ea2b540cbd781b32110e249f6e\",\"lessThan\":\"ec2e157fc9678a9bc411305a25aec3fd337d7efb\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"bbd0d59809f923ea2b540cbd781b32110e249f6e\",\"lessThan\":\"28c5fdce9dd955d2baf5e28987819b6d7cfaf646\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"bbd0d59809f923ea2b540cbd781b32110e249f6e\",\"lessThan\":\"18957373920caf5cdaf5cf32e5d1d7a99ca7700a\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"bbd0d59809f923ea2b540cbd781b32110e249f6e\",\"lessThan\":\"83f5031f2a6a49d696eb4cc0898345d12f9c6451\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"bbd0d59809f923ea2b540cbd781b32110e249f6e\",\"lessThan\":\"8e04823c120b376ef7dab14b60ebf6823aa16c14\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"net/sctp/sm_statefuns.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"2.6.24\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"2.6.24\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.10.265\",\"lessThanOrEqual\":\"5.10.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.216\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.183\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.148\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.101\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.42\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.6\",\"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:H/I:H/A:H\",\"baseScore\":9.8,\"baseSeverity\":\"CRITICAL\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":5.9}]},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/18957373920caf5cdaf5cf32e5d1d7a99ca7700a\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/28c5fdce9dd955d2baf5e28987819b6d7cfaf646\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/5a022ac51ad83b4ce6c898f4b9eefc65bd26b247\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/6caf0e8590c0bf05a76b0d387726adf3a6f3725c\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/83f5031f2a6a49d696eb4cc0898345d12f9c6451\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/8e04823c120b376ef7dab14b60ebf6823aa16c14\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/a129792b3aef15002746c13522781d92ed3522c3\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/ec2e157fc9678a9bc411305a25aec3fd337d7efb\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-09-14T11:48:30+00:00",
      "cve": "CVE-2026-68300",
      "id": "CVE-2026-68300",
      "initial_release_date": "2026-08-10T00:00:00+00:00",
      "product_status:fixed": "453",
      "product_status:known_affected": "140",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: sctp: auth: verify auth requirement when auth_chunk is NULL",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-68300.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-09-13T17:05:25Z",
      "cve": "CVE-2026-68300",
      "id": "CVE-2026-68300",
      "initial_release_date": "2026-08-14T17:14:24Z",
      "product_status:first_fixed": "65",
      "product_status:known_affected": "341",
      "product_status:recommended": "62",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-68300",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-68300.json",
      "version": "7"
    }
  }
}



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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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