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CVE-2026-53246 (GCVE-0-2026-53246)

Vulnerability from cvelistv5 – Published: 2026-06-25 08:39 – Updated: 2026-08-05 12:34
VLAI
Title
sctp: validate cached peer INIT chunk length in COOKIE_ECHO processing
Summary
In the Linux kernel, the following vulnerability has been resolved: sctp: validate cached peer INIT chunk length in COOKIE_ECHO processing When a listening SCTP server processes a COOKIE_ECHO chunk, the cached peer INIT chunk embedded after the cookie is parsed and its parameters are later walked by sctp_process_init() using sctp_walk_params(). However, the chunk header length of this cached INIT chunk was not validated against the remaining buffer in the COOKIE_ECHO payload. If the length field is inflated, the parameter walk can run beyond the actual received data, leading to out-of-bounds reads and potential memory corruption during later parameter handling (e.g. STATE_COOKIE processing and kmemdup() copies). Add a bounds check in sctp_unpack_cookie() to ensure the cached INIT chunk length does not exceed the available data in the COOKIE_ECHO buffer before it is used.
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: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < cc272185c9a9a4b7febc2de52eeaa3d00f19091e (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < edccbf3d63b0a3362bc916ea72edacc1e1ca456a (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 0861615c28de668669d748ef4eb913ea9262d13b (git)
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Linux Linux Affected: 2.6.12
Unaffected: 0 , < 2.6.12 (semver)
Unaffected: 6.18.36 , ≤ 6.18.* (semver)
Unaffected: 7.0.13 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: validate cached peer INIT chunk length in COOKIE_ECHO processing\n\nWhen a listening SCTP server processes a COOKIE_ECHO chunk, the cached\npeer INIT chunk embedded after the cookie is parsed and its parameters\nare later walked by sctp_process_init() using sctp_walk_params().\n\nHowever, the chunk header length of this cached INIT chunk was not\nvalidated against the remaining buffer in the COOKIE_ECHO payload. If\nthe length field is inflated, the parameter walk can run beyond the\nactual received data, leading to out-of-bounds reads and potential\nmemory corruption during later parameter handling (e.g. STATE_COOKIE\nprocessing and kmemdup() copies).\n\nAdd a bounds check in sctp_unpack_cookie() to ensure the cached INIT\nchunk length does not exceed the available data in the COOKIE_ECHO\nbuffer before it is used."
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    "dateReserved": "2026-06-09T07:44:35.394Z",
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      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-53246.json",
      "version": "5"
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      "cve": "CVE-2026-53246",
      "id": "CVE-2026-53246",
      "initial_release_date": "2026-06-26T02:08:47Z",
      "product_status:first_fixed": "2",
      "product_status:known_affected": "519",
      "product_status:recommended": "764",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-53246",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-53246.json",
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  }
}



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