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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            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: auth: verify auth requirement when auth_chunk is NULL\n\nsctp_auth_chunk_verify() returns true unconditionally when\nchunk-\u003eauth_chunk is NULL, silently skipping authentication.\nThis is incorrect when:\n\n1. skb_clone() failed in the BH receive path, leaving auth_chunk\n   NULL. In sctp_endpoint_bh_rcv() asoc is NULL for new\n   connections, so the early sctp_auth_recv_cid() check cannot\n   catch this.\n\n2. 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."
          }
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        "id": "CVE-2026-68300",
        "lastModified": "2026-08-19T17:20:41.187",
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        "published": "2026-08-10T13:20:19.560",
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        "vulnStatus": "Received"
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    "redhat_vex": {
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      "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": "2026-09-18T00:32:29Z",
      "cve": "CVE-2026-68300",
      "id": "CVE-2026-68300",
      "initial_release_date": "2026-08-14T17:14:24Z",
      "product_status:first_fixed": "23",
      "product_status:known_affected": "731",
      "product_status:recommended": "168",
      "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": "10"
    }
  }
}



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Tags
Taxonomy of the tags.





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

Author Source Type Date Other

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.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.