GHSA-55HR-9MVF-6M8F

Vulnerability from github – Published: 2026-08-10 15:33 – Updated: 2026-08-19 18:32
VLAI
Details

In the Linux kernel, the following vulnerability has been resolved:

sctp: fix auth_hmacs array size in struct sctp_cookie

The auth_hmacs array in struct sctp_cookie is supposed to store a complete SCTP_AUTH_HMAC_ALGO parameter, which consists of a struct sctp_paramhdr followed by N HMAC identifiers.

However, the array size was calculated using an extra 2 bytes instead of sizeof(struct sctp_paramhdr), which is 4 bytes. When four HMAC identifiers are configured, the HMAC-ALGO parameter stored in the endpoint is larger than the auth_hmacs buffer in the cookie.

As a result, sctp_association_init() copies beyond the end of auth_hmacs when initializing the association, corrupting the adjacent auth_chunks field. This can lead to an invalid HMAC identifier being accepted and later cause an out-of-bounds read in sctp_auth_get_hmac().

Fix the array size calculation by including the full SCTP parameter header size.

Severity
8.1 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2026-68376"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-10T13:20:30Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: fix auth_hmacs array size in struct sctp_cookie\n\nThe auth_hmacs array in struct sctp_cookie is supposed to store a complete\nSCTP_AUTH_HMAC_ALGO parameter, which consists of a struct sctp_paramhdr\nfollowed by N HMAC identifiers.\n\nHowever, the array size was calculated using an extra 2 bytes instead of\nsizeof(struct sctp_paramhdr), which is 4 bytes. When four HMAC identifiers\nare configured, the HMAC-ALGO parameter stored in the endpoint is larger\nthan the auth_hmacs buffer in the cookie.\n\nAs a result, sctp_association_init() copies beyond the end of auth_hmacs\nwhen initializing the association, corrupting the adjacent auth_chunks\nfield. This can lead to an invalid HMAC identifier being accepted and later\ncause an out-of-bounds read in sctp_auth_get_hmac().\n\nFix the array size calculation by including the full SCTP parameter header\nsize.",
  "id": "GHSA-55hr-9mvf-6m8f",
  "modified": "2026-08-19T18:32:17Z",
  "published": "2026-08-10T15:33:48Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-68376"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0528485f27016a42804abe01aa61b39d85fa803e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0b4414e43e0861d67276031cc21401d7e87de3da"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/317731d01b03c529809df36d3a7d149677a8729d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3aa40c3bccac2312ea7cf97f329190637f972b5d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a8d20ba0ab518c9ccbcde258f25fc1ee6e51d5db"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d0a59ba58578e2b330fff80a44fe519f3ba7d8c7"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e0b5252a59383b77d1b8dbeda00b7184dd95f4d3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ee5e65964f456adfe14d526fba0bd055de98ecf3"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}



Log in or create an account to share your comment.




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.